Three EU countries on Tuesday announced they were launching a dispute mechanism against Iran under the 2015 nuclear deal, accusing Tehran of repeatedly violating the accord while insisting they remained committed to the agreement, AFP reports.

The move by Britain, France and Germany comes as tensions soar between the West and Iran following the killing of top commander Qassem Soleimani in a US strike and the admission by Tehran days later it had accidentally shot down a Ukrainian airliner.

The foreign ministers of the three European nations said Iran had been progressively scaling back its commitments under the deal and defying key restrictions on its nuclear program since May of last year.

"We have therefore been left with no choice, given Iran's actions" to begin the dispute process, their statement said, adding Tehran was not "meeting its commitments".

The 2015 nuclear deal -- known as The Joint Comprehensive Plan of Action (JCPOA) -- has a provision that allows a party to claim significant non-compliance by another party before a joint commission.

If the issue is not resolved at the joint commission, it then goes to an advisory board and eventually to the UN Security Council which could reimpose sanctions.

Iran announced last week that it will abandon the deal amid heightened tensions with the United States over the killing of Soleimani.

However, even before the elimination of Soleimani, Iran had been gradually scaling back its compliance with the 2015 deal in response to President Donald Trump’s withdrawal from the agreement in May of 2018.

Most recently, the Islamic Republic restarted uranium enrichment at the underground Fordow facility in violation of the deal.

"Iran's actions are inconsistent with the provisions of the nuclear agreement and have increasingly severe and non-reversible proliferation implications," the statement by the EU countries said, according to AFP.

At the same time, the three powers also said they "once again express our commitment" to the deal and expressed "determination to work with all participants to preserve it".

"Given recent events, it is all the more important that we do not add a nuclear proliferation crisis to the current escalation threatening the whole region," the statement added.

"Our hope is to bring Iran back into full compliance with its commitments under the JCPOA."

The three countries said they would not join "a campaign to implement maximum pressure against Iran" championed by Trump.

Last week, Trump said "the time has come" for the other co-signatories to the deal to follow him and leave the agreement as well.

France later made clear that it remains committed to the 2015 agreement and "continues to work with the other parties" to the deal, meaning the other signatories -- Britain, Germany, Russia and China along with Iran.