OIL major Shell has reportedly joined BP in refusing to transit the Red Sea and Gulf of Aden, amid further risk reassessments by shipowners today, as Houthi attacks against commercial shipping intensified.

All transits on vessels owned or chartered by Shell have been suspended since US and UK strikes on Houthi land targets last week, according to a Wall Street Journal report, citing sources familiar with the situation.

A London-based spokesman said Shell would not comment. BP paused transits last month.

The changing charterer sentiment underscores the volatility and uncertainty in the Gulf of Aden and Red Sea where there have been 31 attacks by Houthis reported on commercial ships since mid-November, including four in the past four days.

Shell was the world’s second-largest dirty charterer in 2023, according to Poten & Partners data, in addition to managing a fleet of 20 LNG carriers.

Along with BP, Shell accounted for 6.5% of dirty charters covering nearly 600 voyages, according to the New York-based shipbroker.

The decision by two of the biggest Western oil majors with a significant tanker chartering presence comes as the Houthis ramp up attacks on US and European-linked ships today. 

Two vessels reported attacks in the Red Sea, with one struck in the cargo hold in addition to the US-listed Eagle Bulk Shipping’s Gibraltar Eagle (IMO: 9702508) that was struck yesterday in the Gulf of Aden.

Bulk carriers and oil and gas tankers had continued to sail uninterrupted through the trade artery connecting Asia and the Middle East Gulf until the US and UK military strikes.

“The risk is hard to quantify”, one shipping executive told Lloyd’s List, saying that whether individual vessels undertook transits largely depended on the charterer. 

Some were keen to avoid the Red Sea all together, with American and UK oil majors among the most risk adverse. 

Oil traders and Middle Eastern oil companies “were much more aggressive about maintaining traffic through the Red Sea”, they said.

Many chartering agreements were ambiguous about transiting an unsafe area, with little precedent for the current situation of transiting a “warlike area¨ as opposed to being ordered to discharge in a port, they said.

“We can certainly delay and have constructive conversations, but contractually it’s not easy to say no.”

The destruction or disabling of Houthi infrastructure in strikes meant “we generally feel that passage is safer than before Friday”.

“Quite a few” vessels were diverting after pausing for several days awaiting the impact of military attacks on Houthis on land, said another shipowner.

Many now sought to insert clauses with any new deals that involved sailing into the Red Sea, or depending on risk appetite, avoided business.

“How long we will have to pause, we just don’t know whether it will be two hours, two days, two weeks. We have no idea,” they said.

One expressed surprise that the Eagle Bulk vessel attacked yesterday was transiting during the day, with its Automatic Identification System switched on.

“If you want to transit, it is absolutely recommended that you do it at night and you turn your AIS off” they said. 

“And you probably adjust your course and speed to mitigate the risk of ‘dead reckoning’ as a way of latching on to your vessel.”

Greece-based shipowners have also said a reassessment of risk was under way after Houthis today targeted a Greece-owned supramax bulk carrier Zografia (IMO: 9486013).