Iran has detained two US Navy patrol boats, with 10 crewmembers, after they drifted into Iranian waters, according to press reports.

Iran has assured the US that the sailors will be returned to a US Navy vessel in international waters on 13 January.

The two patrol boats reportedly went missing between Kuwait and Bahrain, and were stopped by the Revolutionary Guard 2km inside Iranian waters.

The incident comes at a pivotal moment as Iran is expecting to have nuclear sanctions lifted in the coming days.

US Secretary of State John Kerry made immediate phone calls to Iran’s Foreign Minister Javad Zarif to pressure for the release of the crew, according to press reports.

It appears the US and Iranian governments are trying to resolve the situation quickly, but hardliners in both countries will try to exploit the tension. The government of President Rouhani does not control the Revolutionary Guard, who will see their interests eroded by the removal of economic sanctions.

Relations between Iran and GCC countries have deteriorated sharply in 2016, after the execution by Saudi Arabia of Shia Sheikh Nimr al-Nimr, and the storming of Saudi diplomatic buildings in Iran.

Five GCC countries downgraded or severed diplomatic links with Iran in early January.