William Hague is to make his first visit to Russia since becoming Foreign Secretary in an attempt to rebuild relations with Moscow, it has been announced.
Mr Hague, who will make his visit next month, said the "door is open" to improved relations after several years of difficulty.
"Britain's relations with Russia have been strained by a number of serious issues on which we do not see eye to eye," he said.
"Where we do differ, I shall say so plainly and clearly, while exploring the scope to address those differences.
"The door is open to better relations between Britain and Russia; we shall see if a door opens in return."
Relations with Moscow have been strained since the murder in London in 2006 of former KGB officer Alexander Litvinenko.
The Russians refused to extradite another former KGB man, Andrei Lugovoi, to stand trial for the killing.
Despite the differences, however, Britain has acknowledged the need to work with the Russians on international issues, most notably Iran's nuclear programme.