French President Francois Hollande said Saturday the sale of two Mistral warships to Russia would continue "for now" despite the West's worsening relations with Moscow over the Ukraine crisis.

"The contract was signed in 2011, it is being carried out and will be completed by next October," said Hollande during a press briefing in Germany, where he met with Chancellor Angela Merkel.

Their two-day talks had focused on the situation in Ukraine and they called on both Kiev and Moscow to ensure nothing interferes with crucial presidential elections, set for May 25.

But Moscow's annexation of Crimea in March and the West's fears that other regions of east Ukraine could also join Russia has touched off the worst east-west diplomatic row since the end of the Cold War.

On Thursday, the United States again voiced concern about the 1.2 billion-euro ($1.65 billion) sale of the French warships to Russia as Washington mulled imposing more sanctions on the regime of President Vladimir Putin.

"We have regularly and consistently expressed our concerns about this sale even before we had the latest Russian actions and we will continue to do so," Assistant Secretary for Europe Victoria Nuland told US lawmakers ahead of a visit next week to Washington by French Foreign Minister Laurent Fabius.

In March, Fabius had said that Paris could "cancel the sale" if Russia did not change its policy toward Ukraine following the ouster in February of a pro-Kremlin president and the rise of a new pro-West government in Kiev.

The first of the Mistral warships is due to be delivered in October and the second one, slated for Russia's Black Sea fleet based in Sebastopol on the Crimean peninsula, in 2015.

The Mistral is an advanced helicopter assault ship and France's agreement to sell them to Russia had previously triggered protests not only from the US but also other NATO allies.