Germany, France and Britain pressed Iran on Wednesday to reverse a decision to start enriching uranium to levels beyond the limits of a 2015 nuclear agreement, a move which they said ``risks compromising'' chances of diplomacy with the incoming US administration.

The foreign ministers of the three European nations said in a joint statement that the Iranian activity ``has no credible civil justification.'' They said the enrichment was a clear violation of the 2015 deal between Iran and six world powers and ``further hollows out the agreement.''

The United States unilaterally withdrew from the agreement in 2018, and the remaining countries that signed it with Iran — Germany, France, Britain, China and Russia — have been trying to keep the accord from collapsing.

On Monday, Iran began enriching uranium to levels unseen since the 2015 deal. The decision appeared aimed at increasing Tehran's leverage during US President Donald Trump's waning days in office.

Iran informed the International Atomic Energy Agency of its plans to increase enrichment to 20% last week. Increasing enrichment at its underground Fordo facility puts Tehran a technical step away from weapons-grade levels of 90%.

The purpose of the deal was to prevent Iran from developing a nuclear bomb — something Tehran insists it doesn't want to do. The three European powers have expressed hope that with the change of administrations in Washington, the US might rejoin the agreement.

President-elect Joe Biden has said he hopes to return the US to the deal.

Complicating that goal is that Iran — which is seeking relief from crippling US sanctions — is now in violation of most major restrictions set out in the agreement.

The uranium enrichment move ``undermines the joint commitment'' made on Dec. 21 by participants in the deal to preserve the agreement, the European ministers said in their statement Wednesday.

``It also risks compromising the important opportunity for a return to diplomacy with the incoming US administration,'' the statement said.

``We strongly urge Iran to stop enriching uranium to up to 20% without delay, reverse its enrichment program to the limits agreed in the (agreement) and to refrain from any further escalatory steps which would further reduce the space for effective diplomacy,'' the ministers added.

A decision to begin enriching to 20% purity a decade ago nearly triggered an Israeli strike targeting Iran's nuclear facilities. The tensions only abated with the 2015 deal, which saw Iran limit its enrichment in exchange for the lifting of economic sanctions.