The UK, France and Germany have triggered a dispute resolution mechanism in the Iran's nuclear deal amid tensions in the region. Foreign Secretary Dominic Raab told MPs the UK continues to be committed to the deal, the JCPOA, and that the mechanism was triggered to restore a diplomatic track. The nuclear agreement, reached under former US president Barack Obama, imposed restrictions and monitoring of Iran's nuclear programme in exchange for the lifting of international sanctions. Under President Donald Trump, the US abandoned the deal in 2018 and reimposed crippling economic sanctions. Sky's diplomatic editor, Dominic Waghorn, says the latest move by the European countries aims at buying time to try and resuscitate a deal that is currently on life support. If the dispute is not resolved, the deal will be pronounced dead. Waghorn says, however, that the deal cannot be fully revived until America can be persuaded to return to the deal - which is currently out of the question. Mr Raab told the House of Commons: "The UK, France and Germany will remain committed to the deal and will approach the DRM (dispute resolution mechanism) in good faith, striving to resolve the dispute and bring Iran back into full compliance with its JCPOA (Iran nuclear deal) obligations." But Mr Raab was forced to deny he and the prime minister are on different pages with the deal, after Boris Johnson had floated the idea of a new deal negotiated by Donald Trump. Mr Johnson spoke to BBC Breakfast about the existing deal, saying the US saw it as "flawed" but that Mr Trump, whose negotiating skills he complimented, should replace it with his own deal if he doesn't like it. Mr Raab said Mr Johnson was fully committed to the deal but open to a broader initiative to address concerns. Iran's Foreign Ministry spokesman Abbas Mousavi responded in a statement which said: "The Islamic Republic of Iran, as in the past, has complete readiness to support any (act of) goodwill and constructive effort to save this important international agreement." He dismissed the latest move by the Eurpean powers as "passive" action. It comes after Iran's president said the downing of a plane in Tehran was an "unforgivable error" and "all those involved will be punished." In a televised speech on Tuesday, Hassan Rouhani said the "tragic event" would be investigated thoroughly, saying "one person cannot be solely responsible for the crash". An undisclosed number of suspects accused of a role in the downing of the plane have been arrested, Iran said.