Satellite imagery revealed a number of oil tankers vacating the waters around Iran’s key Kharg Island oil loading terminal, amid fears of an Israeli counterattack on Tehran’s energy infrastructure.

“The National Iranian Tanker Company (NITC) appears to be fearing an imminent attack by Israel. Their empty VLCC supertankers vacated the country’s largest oil terminal, Kharg Island, yesterday,” tracking firm Tanker Trackers wrote in a post on the X social media platform on Thursday evening.

Markets have been on edge over the possibility of an Israeli retaliation, after Iran launched a missile attack against the Jewish state earlier this week.

Satellite imagery captured by the European Space Agency’s Copernicus Sentinel-1 mission on Sept. 25 shows a number of VLCC (very large crude carrier) supertankers in the waters around Kharg Island, Iran’s principal oil export terminal. VLCC tankers are specifically designed to transport large volumes of crude oil.

Imagery of the same location on Oct. 3 — two days after Iran launched a volley of around 180 missiles at Israel for the killing of Hezbollah leader Hassan Nasrallah — shows an empty sea around Kharg Island, with no ships in sight.

CNBC could not independently verify the footage.

Iranian tankers are known for frequently switching off their transponders and manipulating their automatic identification system (AIS) in order to conceal their movements to skirt U.S. sanctions on the country’s oil exports. This is a different kind of development, says Samir Madani, co-founder of TankerTrackers.com

His analysis of the satellite imagery located the Iranian tankers as currently being “in the middle of the Persian Gulf, west of the island,” he told CNBC.

The December delivery contract of global benchmark Brent was trading at $78.49 per barrel on Friday at 9:30 a.m. in London, up 1.1% from the Thursday close. The front-month November U.S. West Texas Intermediate futures were trading at $74.49 per barrel, higher by 1% from the previous day’s settlement.

Oil prices have jumped more than $5 a barrel since the start of the week amid intensifying fears that Israel could launch an attack on Iran’s energy infrastructure.

The rally, which puts crude futures on track for gains of around 8% week-to-date, has surprised many market observers in that it appears to be somewhat subdued given what’s at stake.

Energy analysts have questioned whether oil markets are being too complacent about the risk of a widening conflict in the Middle East, particularly given that the fallout could disrupt oil flows from the key exporting region. Iran, which is a member of OPEC, is a major player in the global oil market. It’s estimated that as much as 4% of global supply could be at risk if Israel targets Iran’s oil facilities.

For some analysts, the reason crude prices have yet to move even higher is because the oil market is short. This refers to a trading strategy in which an investor hopes to profit if the market value of an asset declines.

“There is a very large short position, not only in oil, you [also] see it in equities. In general, the investors don’t like this space. Why? They are concerned about a big oil supply glut next year,” Jeff Currie, chief strategy officer of energy pathways at Carlyle, told CNBC’s “Squawk Box Europe” on Wednesday.

“When we look at the situation today, it is starkly different. Inventories are low, curve is backwardated, demand is middling, it’s not great but now you have [China’s] stimulus package on top of that, and you still have the OPEC production cuts,” Currie said.

“On top of that, we’ve thrown in potential conflict in the Middle East that could take out some energy facilities, so the near-term outlook is positive, which is why the front of the curve is strong, but it is being weighed down on the back end over the fears of this big oil supply glut,” he added.

The market is backwardated, or in backwardation, when the futures price of oil is below the spot price. The opposite structure is known as contango.

International benchmark Brent crude futures with December expiry traded 0.1% lower at $77.54 a barrel on Friday, while U.S. West Texas Intermediate futures stood at $73.65, down 0.1% for the session.

Oil’s biggest move this week came on Thursday, when prices popped more than 5% following comments from U.S. President Joe Biden over a possible retaliatory move from Israel following Iran’s ballistic missile attack earlier in the week.

Asked by reporters whether the U.S. would support an Israeli strike on Iranian oil facilities, Biden said: “We’re discussing that. I think that would be a little – anyway.” The president added that “there’s nothing going to happen today.”

CNBC has reached out to the White House for further comment.

Tamas Varga, an analyst at oil broker PVM, told CNBC via email on Thursday that the oil market was pricing in some risk premium given the geopolitical concerns.

“This is why oil is stable-to-higher, equities are weakening, and the dollar is strong. These fears, however, will be greatly alleviated in [the] coming days unless oil supply from the region or traffic through the Strait of Hormuz are materially impacted,” he added.

Situated between Iran and Oman, the Strait of Hormuz is a narrow but strategically important waterway that links crude producers in the Middle East with key markets across the world.

“Under this scenario underlying fundamentals will become the driving force again and these fundamentals are anything but encouraging,” Varga said.

Israeli Prime Minister Benjamin Netanyahu on Tuesday pledged to respond with force to Iran’s ballistic missile attack, insisting Tehran would “pay” for what he described as a “big mistake.” His comments came shortly after Iran fired more than 180 ballistic missiles at Israel.

Speaking during a visit to Qatar on Thursday, Iranian President Masoud Pezeshkian said his country was “not in pursuit of war with Israel.” He warned, however, of a forceful response from Tehran to any further Israeli actions.

Bjarne Schieldrop, chief commodities analyst at the Swedish bank SEB, said that oil prices were surprisingly steady given the high stakes.

“I think it is definitely a little bit about short covering, but [the price rally] is surprisingly weak … given the scenarios that might play out in the Middle East,” he told CNBC’s “Street Signs Europe” on Thursday.

Schieldrop said Brent crude prices had largely traded between $80 to $85 for around 18 months or so, before dipping below $70 in September. He described the oil contract’s recent move higher as “very meager,” especially given the “potentially devastating scenarios in the Middle East.”

— CNBC’s Spencer Kimball contributed to this report.

Oil prices could shoot up $20 per barrel if Iranian production sees a hit resulting from Israeli retaliation, according to Goldman Sachs.

U.S. crude futures rose around 5% on Thursday and ticked higher again Friday morning on concerns that Israel could strike Iran’s oil industry in retaliation for Tehran’s missile attack this week.

It is estimated that “if you were to see a sustained 1 million barrels per day drop in Iranian production, that you would see a peak boost to oil prices next year of around $20 per barrel,” Daan Struyven, Goldman Sachs’ co-head of global commodities research, told CNBC’s “Squawk Box Asia” on Friday.

This is under the assumption that oil cartel OPEC+ refrains from responding by increasing production, Struyven said.

Should key OPEC+ members such as Saudi Arabia and UAE offset some of the production losses, oil markets could see a smaller boost of slightly less than $10 barrel, he added.

Since the Israel-Hamas armed conflict began on October 7 of last year, there had been limited disruptions to the oil market, with prices remaining under pressure due to increased production from the U.S. and sluggish demand from China.

However, the sentiment could be shifting this week. U.S. crude oil prices just saw a third consecutive session of gains after Iran launched a ballistic missile attack on Israel, heightening tensions in the region. In recent days, industry watchers have sounded the alarm, warning of a real threat to supply.

Iran, which is a member of OPEC, is a key player in the global oil market. It produces almost four million barrels of oil per day, and an estimated 4% of the world’s supply could be at risk if Iran’s oil infrastructure becomes a target for Israel as the latter considers a countermove. 

Saul Kavonic, senior energy analyst at MST Marquee, raised the potential of Iran’s Kharg Island, which is responsible for 90% of the country’s crude exports, becoming a target.

“The bigger concern, “is this the kind of a much more imminent beginning of a wider conflagration of the conflict which could impact transit through the Strait of Hormuz,” he added.

If Israel hits Iran’s oil industry, supply disruptions in the Strait of Hormuz could become of concern, other analysts echoed.

Iran has previously threatened to disrupt flows through the Strait of Hormuz if its oil sector is impacted.

The strait between Oman and Iran is a crucial channel through which approximately one-fifth of the world’s daily oil production passes, according to the U.S. Energy Information Administration. This strategically significant waterway connects crude oil producers in the Middle East with major global markets.

Asked by reporters Thursday if the U.S. would support an Israeli strike on Iranian oil facilities, U.S. President Joe Biden said: “We’re discussing that. I think that would be a little – anyway.” Oil analysts think those remarks were the catalyst that moved prices higher.

CNBC has reached out to the White House for comment.

“In the case of a full-scale war, Brent would likely soar above USD100/bbl, with any potential shut-in of the strait threatening prices of USD150/bbl or more,” Fitch Solutions’ BMI wrote in a note published Wednesday. 

While the probability of a full-scale war remains “relatively low,” the risks of a misstep by either side are now elevated, BMI’s analysts stated.

Although some industry analysts believe that OPEC+ has enough spare capacity to compensate for a disruption in Iranian exports if Israel targets its oil infrastructure, the world’s spare oil capacity remains largely concentrated in the Middle East, especially among the Gulf states, which could be at risk if a larger conflict worsens.

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