A Russian journalist and Kremlin critic, reported to have been shot dead in Ukraine, has appeared alive at a news conference.

Arkady Babchenko was earlier reported to have been killed in his apartment building in the Ukrainian capital Kiev.

But in a stunning development, he appeared alongside Ukrainian security officials in a news conference broadcast live on Ukrainian television.

Ukraine's Security Service suggested it had staged the murder.

Writing on Twitter, the security service said it had received prior warning about the attempted murder of Babchenko and decided to conduct an operation to collect evidence of terrorist activity by the Russian special services on Ukrainian territory.

Earlier, Ukrainian state news agency Ukrinform had said that Babchenko, 41, was shot in the back and died in an ambulance, citing his friend and supervisor, Ayder Muzhdabaev, deputy general manager of Ukrainian TV channel ATR.

Police in Kiev said Babchenko's wife found him outside their apartment.

It is not immediately clear whether Babchenko's wife and friend were aware of the security operation.