The controversial sale of two high-tech warships to Russia is "not on the agenda", France's defence minister said on Monday, despite the ceasefire agreed in Ukraine last week.

"It's not on the agenda," Jean-Yves Le Drian told French radio.

"The President of the Republic has decided that we should not deliver these warships because the ceasefire was not in place, because there were security risks -- including security risks in Europe -- and because Russia was breaking its international agreements on borders," stressed Le Drian.

"At the moment, the ceasefire is fragile, the peace process will no doubt start soon," added the minister.

French President Francois Hollande said last year the "conditions are not right" to deliver the two Mistral-class warships, despite their 1.2-billion-euro ($1.4-billion) price tag.

He has since said the delivery of the warships is suspended "until further notice."

Paris faces hefty fines if it breaches the contract with Russia, but is under pressure from its allies around the world if it hands over the hot-button technology at a time of Moscow's growing militancy and the Ukraine crisis still raging.

A ceasefire agreed in Minsk last week is "generally" holding, the leaders of France, Germany, Ukraine and Russia said on Sunday, but there are still pockets of violence, especially around the key railway hub of Debaltseve.