The British minister for the Middle East had “open, frank and constructive” talks about rising tension in the region with Iranian government representatives in Tehran. “I reiterated the UK’s assessment that Iran almost certainly bears responsibility for recent attacks on tankers in the Gulf of Oman,” said Andrew Murrison, British minister for the Mena region. “Such activity, which carries a high risk of miscalculation, needs to stop to allow for immediate de-escalation of rising tension.” US President Donald Trump said on Sunday that he was not seeking war with Tehran after a senior Iranian military commander warned any conflict in the Gulf could spread uncontrollably and threaten the lives of US troops. Mr Murrison said he reaffirmed Britain’s determination to maintain the nuclear deal Iran signed with world powers in 2015. He met government representatives including Vice President Masoumeh Ebtekar, Deputy Foreign Minister Abbas Araghchi and the Deputy Head of the Atomic Energy Organisation of Iran, Behrouz Kamalvandi. Tehran said in May it would reduce compliance with the pact in protest against the US decision to pull out of the agreement and reimpose sanctions last year. “I was clear that Iran must continue to meet its commitments under the deal in full, including the limits imposed on its low-enriched uranium stockpile,” Mr Murrison said. He said he had also pressed again on behalf of the British government for the “urgent and unconditional release” of British-Iranian aid worker Nazanin Zaghari-Ratcliffe. Ms Zaghari-Ratcliffe was arrested in April 2016 at a Tehran airport as she was flying back to Britain with her daughter after a family visit. She was sentenced to five years in jail after being convicted of plotting to overthrow Iran’s clerical establishment, a charge denied by her family and the Thomson Reuters Foundation.