ALGIERS: France said Wednesday it will expel Algerian diplomats in response to Algeria’s decision to do the same, escalating a diplomatic standoff.

The Ministry for Europe and Foreign Affairs said in a statement it had summoned Algerian officials to inform them of the decision, describing it as “strict reciprocity” after 15 French officials were expelled from Algiers on Sunday.

France did not say how many Algerians holding diplomatic passports had been expelled. It called on Algerian authorities to “demonstrate responsibility and to return to a demanding and constructive dialogue that had been initiated by our authorities, in the interest of both countries.”

“The Algerians wanted to send back our agents; we are sending theirs back,” French Foreign Minister Noël Barrot said on Wednesday, speaking Wednesday to French broadcaster BFMTV.

The measures are the latest sign of deteriorating relations between France and Algeria. They go against a 2013 deal allowing individuals with diplomatic passports to travel between the countries without needing visas.

Algeria said it expelled French officials on Sunday because France had broken procedures, including in how it assigned new diplomats to replace a different set that were expelled last month.

Despite economic ties and security cooperation, France and Algeria for decades have clashed over issues ranging from immigration to the painful legacy of French colonialism.

Tensions flared last year when France shifted its longstanding position and backed Morocco’s plan for sovereignty over disputed Western Sahara. Algeria views the Morocco-controlled territory as Africa’s last colony and supports the pro-independence Polisario Front materially and politically.

The tensions jeopardize more than $12 billion in annual bilateral trade and could create hurdles for the hundreds of thousands of Algerian-born residents of France who travel between the countries.