Russian opposition leader Alexei Navalny has said he will fly back to Russia from Germany where he has been convalescing after being poisoned.

He said he will return on 17 January.

Mr Navalny, one of Russian President Vladimir Putin's leading critics, was airlifted to Germany for treatment in August after collapsing on a plane in what Germany and other Western nations say was an attempt to murder him with a Novichok nerve agent.

Russian authorities deny any involvement in the incident. 

Mr Navalny, 44, wrote on Instagram that he had probably almost fully recovered and said it was time to return to Russia despite various legal threats hanging over him.

He said it was never a question for him as to whether he would or would not return. 

President Putin has rejected reports that his country's security services were behind the poisoning of Alexei Navalny.

The opposition leader would not be alive if they had been, he told reporters at his annual end-of-year press conference

The Russian leader said that Mr Navalny was supported by US special services, then Russia should of course tail him.

"But this does not at all mean that it is necessary to poison him. Who needs him?" President Putin said.

If the Russian special services had wanted to poison Mr Navalny, "they would have taken it to the end," he said.

In response to the poisoning, the European Union imposed entry bans and froze the bank accounts of six people suspected of being responsible, including FSB chief Alexander Bortnikov.