Tehran, Nov 30, 2018 (AFP)

Iran said Friday the European Union must be given more time to set up a trade mechanism meant to circumvent reimposed US sanctions on Tehran, but warned it could not "wait forever".

Brussels is working on a payment system to continue trade and business ties with Iran after the US ditched a landmark 2015 nuclear deal with Tehran earlier this year and reintroduced a raft of sanctions on the country.

"Europe's efforts for implementing a financial mechanism are continuing despite mounting US pressure," Iran's deputy foreign minister Abbas Araghchi told the official IRNA news agency.

"We believe that Europe must be given more time ... they have so far been unable to introduce operational measures, but we are not supposed to wait forever," he added.

The US sanctions aim to cut off Iran's banks from international finance and significantly reduce its oil exports.

The EU hopes its "special purpose vehicle" (SPV) announced in September will keep the nuclear deal alive and pursuade Tehran to stay on board by giving companies a way of trading with Iran without fear of US sanctions.

But Brussels is struggling to find a host for the SPV and many EU countries are fearful of repercussions from US President Donald Trump's administration.

"Americans are out to block all paths and have already started pressuring countries aiming to implement the mechanism and work with it," said Araghchi, refusing to comment on potential SPV hosts due to the "sensitivity" of the issue.

Austria, Belgium and Luxembourg have already rejected hosting the special payment system, Bloomberg News reported.

Araghchi said Iran will stay in the nuclear deal as long as it meets Tehran's interests, but will "make a different decision" the moment it no longer does.