BP Plc (NYSE: BP) and Iran's state-run oil company received a license from the U.S. Treasury last year to operate their joint gas field in the North Sea following the lifting of Western sanctions on Tehran, BP said April 6.

Production at the Rhum Field was suspended in 2010 when Europe imposed sanctions on Iran over its nuclear program and only resumed four years later after Britain agreed to set up a temporary management scheme whereby all revenue due to Tehran would be held until sanctions were lifted.

Following the removal of European Union and United Nations sanctions on Iran in January 2016, the temporary management scheme ceased.

Iran regained control of its stake and on Sept. 29, 2016, BP obtained a license from the U.S. Treasury, through its sanctions enforcement arm—the Office of Foreign Asset Control (OFAC), to continue operations at the field, BP said in its 2016 annual report.

BP, which was founded more than a century ago as the Anglo-Persian oil company, has multiple business operations in the United States and therefore needs an OFAC license to avoid potential breaches of existing U.S. sanctions.

Last year BP created an executive committee to explore business in Iran, which would exclude its American CEO Bob Dudley in a bid to avoid potential sanctions violations.

London-based BP recorded a net profit of $31.6 million in 2016 from its 50% stake in the field, which supplies around 4% of Britain's gas demand.

"BP currently intends to continue to hold its ownership stake in the Rhum joint arrangement and act as operator," it said in the annual report.

While international sanctions on Iran were removed more than a year ago, the U.S. has held separate measures in place and President Donald Trump's administration has promised a tough line.

BP did not specify for how long the Rhum field license was valid.

Previous U.S. President Barack Obama tried to encourage non-U.S. companies and non-U.S. banks to increase trade with Iran, although Tehran said Washington did not do enough to ease its access to international financial markets and banks for vital capital after years of isolation.

Offshore