European Union Foreign Policy Chief Josep Borrell on Tuesday announced that Germany, France and the UK have launched action under the Iran nuclear agreement to pave the way for possible sanctions in response to Tehran's fifth and final step in reducing its commitments.

Joseph Borrell as the Chief of EU foreign policy will oversee the process of the Dispute Resolution Mechanism as part of the nuclear agreement officially known as the Joint Comprehensive Action Plan (JCPOA).

The European sides of the nuclear agreement were given "no choice" but to trigger the dispute process, the three countries said in a joint statement released on Tuesday but added that they were leaving the door open for diplomacy and their move did not mean they were joining President Trump's "maximum pressure" campaign against Iran.

In a statement later on Tuesday, Iran's Foreign Ministry Spokesman Abbas Mousavi said the European sides of the JCPOA "who claim they have triggered the dispute mechanism with good intentions and want to rescue it" must prepare themselves for consequences if they continue to "succumb to America's wishes". As before, Iran is fully prepared to show goodwill and support any constructive initiative aiming to rescue the nuclear agreement, Mousavi added.

Iran announced on January 5 that it would no longer recognize any limits on the number of its centrifuges or level of uranium enrichment and would continue its nuclear program only on the basis of "the country's technical needs" but insisted that this did not mean the nuclear agreement and the steps taken were "reversible".

On Tuesday Reuters reported that two diplomats have said the European 3 would notify the European Union later on Tuesday that they were triggering the dispute resolution mechanism and will inform the other parties – Russia, China and Iran, of their decision.

Under the mechanism, there will be 15 days to resolve the differences but the deadline can be extended by consensus. If differences are not resolved sanctions under previous UN resolutions can be re-imposed.

Iran concluded the nuclear agreement in 2015 with Britain, France, Germany, Russia and China and the United States, collectively known as P5+1, but in 2018 Washington withdrew from the deal unilaterally and re-imposed sanctions on Iran.

On Tuesday hours after Britain insisted it still supports the "shell" of the JCPOA British Prime Minister Boris Johnson said it is flawed and he wants to work with the U.S. and Britain's other allies to replace it.

"If we're going to get rid, we need a replacement. Let's replace it with the Trump deal," Johnson said.