ARKADY Babchenko, the dissident Russian journalist who faked his own death in Ukraine, says he felt he had to undertake the ruse because he feared he would share the fate of poisoned former Russian spy Sergei Skripal.

His second press conference came as a Kiev court granted a request by prosecutors on Thursday to detain a suspect for two months in what Ukrainian authorities say is the plot to murder Babchenko.

Ukrainian officials reported on Tuesday night that Babchenko, a Kremlin critic, had been gunned down in his apartment building in Kiev.

A day later, Babchenko appeared in public alive, and Ukrainian security officials said they had faked his death to thwart and expose what they described as a Russian plot to assassinate him.

That drew criticism from some media defenders and commentators who questioned whether the ruse and the false outpouring of grief and finger-pointing at Russia it generated had undermined credibility in journalism itself and in Kiev, handing the Kremlin a propaganda gift in the process.

Babchenko hit back in a joint interview in Kiev on Thursday, saying that he had gone along with the ruse, organised by Ukrainian security officials, because he feared for his life.

"Everyone who says this undermines trust in journalists: what would you do in my place, if they came to you and said there is a hit out on you?" Babchenko said.

He said that when Ukrainian security officials had approached him with information about a Russian plot to kill him, "my first reaction was: 'To hell with you, I want to pack a bag and disappear to the North Pole.'

"But then I realised, where do you hide? Skripal also tried to hide."

British authorities say Skripal, a former Russian double agent, was poisoned in March with a military-grade nerve agent in the English city of Salisbury where he lived after leaving Russia in a spy swap.

Babchenko disclosed how he had helped fake his own death. He said a make-up artist had come to his apartment to give him the appearance of a shooting victim, that he was given a T-shirt with bullet holes in it to wear, and that pig's blood was poured over him.

He played dead, he said, while medical teams - who were in on the ruse - took him to hospital in an ambulance and then certified him as dead and sent him to a morgue.

"Once the gates of the morgue closed behind me, I was resurrected," Babchenko said, saying he had then washed off the fake blood and dressed himself in a sheet.

"Then I watched the news and saw what a great guy I had been," he said, referring to media tributes to him after his death was widely reported.

Meanwhile Borys Herman, the co-owner of a weapons manufacturer, appeared in court denying that there was ever any intent to kill Babchenko and saying that he had acted in Ukraine's interests.

Herman said he had been contacted by someone close to the Kremlin about plans to kill Babchenko but that he instead turned this information over to the Ukrainian authorities and worked on counter-intelligence operations with them.

"We knew perfectly well that there would be no killing," he said. "This was done only for the benefit of Ukraine."

Prosecutors said they had evidence that Herman had handed over $US15,000 ($A20,000) to pay someone to kill Babchenko.