Announcing a new doctrine of "forward deterrence", Macron said the plans involving partners including Germany, Britain and Poland would "complicate the calculations of our adversaries".

"We must strengthen our nuclear deterrent in the face of multiple threats, and we must consider our deterrence strategy deep within the European continent," he said in a speech at France's Ile Longue nuclear submarine base.

He spoke as Russia's war against Ukraine grinds into its fifth year, with European nations worried about Washington's wavering commitment to their security at the same time as the attacks launched by the United States and Israel on Iran threaten to destabilise the Middle East.

The Netherlands, Belgium, Greece, Sweden and Denmark could also all take part. Here is how the partner nations have reacted so far:

- Denmark -

Ruling out French atomic bombs on Danish soil, Denmark's Prime Minister Mette Frederiksen said it was "unfortunately" necessary for Europe to discuss deterrence because of a threat from Moscow.

"It is about being at the table and so having better access to information and to strategic decisions," she said at a press conference.

"This cooperation must respect current Danish nuclear policy," she added.

- Germany -

In a joint statement with France, Germany said it would participate in French nuclear exercises -- but it added that the United States should keep its nuclear forces on the continent.

"France and Germany have agreed to take first concrete steps beginning this year, including German conventional participation in French nuclear exercises and joint visits to strategic sites," the statement said.

"This Franco-German cooperation is based on the shared understanding that the nuclear dimension of deterrence remains a cornerstone of European security, relying on US extended deterrence," it added.

- Greece -

Asked about reports of the plans, Greek government spokesman Pavlos Marinakis refused to give details but said work was underway.

"I don't wish to say any more at this stage, but the direction described regarding a common European policy on this very important issue is indeed the one mentioned," he said.

"More information will be available in the coming days and weeks," he added.

- Poland -

Polish Prime Minister Donald Tusk welcomed the plans and said they would make his country safer.

"Poland is in talks with France and a group of closest European allies on the programme of advanced nuclear deterrence," Tusk wrote in a post on X.

"We are arming up together with our friends so that our enemies will never dare to attack us."

Poland's nationalist President Karol Nawrocki recently expressed support for a homegrown deterrent without going into details on any proposed scheme.

- Sweden -

Swedish Prime Minister Ulf Kristersson said his country viewed Macron's suggestion "positively".

"Naturally, we would most like to see a world completely free of nuclear weapons," he said.

"But as long as Russia has these weapons and threatens its neighbours, democracies must be able to deter attacks and safeguard our own security and freedom."

burs-vbw/yad