Iran called on the British government to respond to the release of 15 military personnel with goodwill.
"We played our part and we showed our goodwill. Now it is up to the British government to proceed in a positive way," Iran's ambassador to Britain, Rasoul Movahedian, told the Financial Times in an interview.
US forces in Iraq have arrested a number of Iranians, including diplomats, in the past and are still holding five. Washington accuses Tehran of aiding militants fighting US forces in Iraq. Iran denies the charge.
Movahedian said the release of the Britons was not linked to any other case, but added: "If (the British) want to be helpful and use their influence we will welcome that ... We will welcome in general any steps that could defuse tensions in the region."
Some media reports during the two-week standoff over Tehran's seizure of the Britons that ended on Thursday said Iran wanted the five Iranians freed in return for releasing the 15.
Movahedian said it was a "mutual task" for Iran and the world's major powers to "glean the fruits" of Tehran's decision to release the Britons.
He said he would welcome recognition by the UN Security Council's five permanent members - the United States, Britain, France, Russia and China - of what Iran says is its right to enrich uranium in its nuclear programme for peaceful purposes.
"That's the prime issue for Iran and I think that could help set a new basis for our future relations with Western countries," he said.
"We share in the British people's happiness (over the release of the 15) and we believe it is the right time for the British government to affirm its willingness to establish sensible lines of communication with Iran."