British Foreign Secretary Boris Johnson

British Foreign Secretary Boris Johnson is to travel to Russia in the coming weeks for high-level political talks, his office said Saturday.

It will be the first time a British minister has been to Moscow for an official visit in more than five years and could signal a potential thaw in Anglo-Russian relations after years of antagonism.

A Foreign Office spokeswoman stressed that the visit was not a return to “business as usual,” saying Britain’s approach to Russia was “engage, but beware.”

Relations with Russia soured after Britain sought to prosecute suspects in the killing of Kremlin critic and former spy Alexander Litvinenko, murdered by radiation poisoning in London in 2006.

Britain has also been one a fervent supporter of Western sanctions against Moscow over Russia’s role in the Ukraine crisis.

Johnson was invited by his Russian counterpart Sergei Lavrov, and more detailed timings will be announced later.

“Our policy toward Russia is to ‘engage but beware’ and the visit is entirely consistent with this approach,” the spokeswoman said.

“Discussions will focus on the UK-Russia relationship and current international issues including Syria and Ukraine, where we continue to have significant differences.

“This is not a return to business as usual and the foreign secretary will continue to be robust on those issues where we differ.”

The spokeswoman said a visit had been in the pipeline since British Prime Minister Theresa May met Russian President Vladimir Putin at the G20 Summit in Hangzhou, China in September 2016.

Johnson and Lavrov held their first telephone talks in August the same year.

Johnson has described Putin as a “ruthless and manipulative tyrant,” and compared his looks to the Harry Potter character Dobby the House Elf. Yet he has called for greater cooperation with the Russian leader in the battle against the Islamic State jihadist group in Syria.

Johnson has recently hinted at a shift in Syria policy, saying President Bashar Assad could be allowed to run for re-election and mentioning a possible “arrangement” with regime ally Russia.

Britain has been one of the harshest critics of Russia’s Syria policy and the Assad regime, saying the president’s departure is a precondition for any resolution to the conflict.