France's controversial warship deal with Russia is hitting the headlines again, with a cacophony of statements and denials after a Russian minister published a French invitation to the hand-over ceremony.

Russian deputy prime minister Dmitry Rogozin on Wednesday (29 October) published a letter on his Twitter page by the French constructor of Mistral warships, supposedly inviting Russian authorities to the ceremony in St Nazaire on 14 November.

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He tweeted that the Russian state-owned arms company Rosoboronexport was invited for the delivery of one ship and for next steps on construction of the second one in the contract.

But a spokesperson of the constructor (DCNS) said a few hours later that the Mistral delivery has not yet been confirmed.

"DCNS wants to clarify that it is still waiting for the governmental export authorisations needed for such a transfer to take place," the spokesman said, according to Le Monde.

Meanwhile, French budget minister Michel Sapin told RTL radio that the "conditions are not met yet for the delivery of the Mistral ships to Russia”.

He explained that these conditions would be a "return to normality in Ukraine and that Russia plays a positive role".

"Things are going better but there are still concerns," Sapin said.

A final decision by the French president, Francois Hollande, on the delivery of the €1.2bn warships will be taken in November, if Russia sticks to the peace plan and "fully observes the ceasefire agreement," according to the French defence minister, Jean-Yves Le Drian.

The Mistral deal is seen as an embarrassment for the EU's joint stance on Russia in reaction to the war in Ukraine.

Its history is also controversial: negotiations started in 2008, shortly after Russia attacked Georgia, with then-French president Nicolas Sarkozy shuttling back and forth between Moscow and Tbilisi to negotiate a cease-fire.

Sarkozy sealed the €1.2bn deal in 2011, with the two warships being built in St Nazaire, where Russian sailors have been undergoing training since the summer despite the EU-Russia sanctions confrontation.

The two ships are called Vladivostok and Sebastopol - the latter being the name of the Crimean port which was annexed by Russia in March.

Vladivostok is to be delivered by the end of this year, after construction and testing ended in March.

Some 360 Russian marines have already started exercises and training on board, Le Parisien reports. The delivery of Sevastopol is due in 2016.

Russian bombers

The Mistral debacle comes at a bad time, as Nato on Wednesday said it had intercepted 19 Russian aircraft flying close to European airspace.

Russian bombers, fighter jets, and tanker aircraft were detected over the Atlantic Ocean and the North, Black and Baltic seas, Nato said.

There were no incursions into Nato or EU airspace, but in at least one of the four incidents, the aircraft had switched off their transponders and had not communicated their route to air traffic controllers, potentially creating a risk for civilian planes.

Fighter jets from Norway, Britain, Portugal, Turkey, Germany, Denmark, Finland and Sweden were involved in responding to the Russian aircraft, Nato said.

"It's concerning because it's moving in the wrong direction. It's not helping to de-escalate the situation in Ukraine. It's not helping to improve relations between Nato and Russia. It’s not helping anybody," a US official told Washington Post.