The widow of poisoned spy Alexander Litvinenko will meet Theresa May today.
Marina Litvinenko will have private talks with the Home Secretary a week after an official inquiry into her husband's death concluded that his killing was "probably approved" by Russian president Vladimir Putin.
Following the publication of the inquiry report, which sparked a diplomatic row and calls for the UK to impose sanctions against Moscow, Mrs May said the findings were "deeply disturbing".
Ahead of the meeting, a Home Office spokeswoman said: "The Home Secretary made clear that she would meet with Mrs Litvinenko and listen very carefully to what she has to say.
"We are not going to confirm details or timings of what is a private meeting."
Mrs Litvinenko called on Prime Minister David Cameron to impose "targeted economic sanctions and travel bans" against individuals, including Mr Putin.
Moscow has dismissed the findings, describing the inquiry as a political "whitewash".
Earlier this week Russian foreign minister Sergei Lavrov warned it would "certainly worsen" relations between London and Moscow and even suggested that British officials could be sued for slander.
The Government has announced financial sanctions against Andrei Lugovoi and Dmitri Kovtun, who allegedly carried out the killing. Both deny involvement.
Mr Litvinenko, a Russian dissident who became a British citizen, died aged 43 in November 2006, three weeks after he drank tea laced with polonium 210 at the Millennium Hotel in Mayfair, central London.