Smoke billows from the town of Ras al-Ain as Turkey continues the assault on Kurdish-held border towns in northeastern Syria | Nazeer Al-Khatib/AFP via Getty Images Germany, France to curb arms sales to Turkey over Syria operation British PM Johnson expresses ‘grave concern’ to Erdoğan as European worries grow.

Germany and France said Saturday they would not export any more weapons to Turkey that could be deployed in the country's military operation in Syria.

“Against the backdrop of the Turkish military offensive in northeastern Syria, the federal government will not issue new permits for all armaments that could be used by Turkey in Syria," German Foreign Minister Heiko Maas told newspaper Bild am Sonntag.

France announced a similar measure on Saturday evening and reiterated its condemnation of the Turkish offensive.

"France has decided to suspend all export projects of armaments to Turkey that could be deployed as part of the offensive in Syria," the French government said in a statement. "This decision takes effect immediately."

European governments and the European Union as a whole have spoken out against Turkey's military offensive against Syrian Kurdish forces since it began on Wednesday.

British Prime Minister Boris Johnson expressed "grave concern" about the offensive to Turkish President Recep Tayyip Erdoğan in a phone call on Saturday evening, the U.K. government said.

A statement from Johnson's office said "the Prime Minister was clear that the UK cannot support Turkey’s military action. He urged the President to end the operation and enter into dialogue."

Germany's Maas told Bild am Sonntag that Berlin has been taking a very restrictive line on arms exports to Turkey since 2016, and particularly after a Turkish military operation in the northern Syrian region of Afrin last year.

Last year, German armaments deliveries to Turkey amounted to €242.8 million — almost a third of all the country's exports of weapons of war, according to the newspaper.

Rym Momtaz, Joshua Posaner and Kate Day contributed reporting.

This article has been updated.