Boris Johnson will travel to Poland on Thursday and Liz Truss will visit Moscow as part of a concerted effort to address the Ukraine crisis.
Reports indicated Mr Johnson will meet Prime Minister Mateusz Morawiecki and President Andrzej Duda as part of an effort to reassure eastern European allies about the UK’s support.
The Foreign Secretary was flying to Moscow on Wednesday for talks with counterpart Sergei Lavrov during a two-day trip.
Her visit is the first by a UK Foreign Secretary for more than four years and comes with tensions high over the build-up of Russian forces near the border with Ukraine.
The UK is determined to stand up for freedom and democracy in Ukraine
Defence Secretary Ben Wallace is also expected to visit Moscow this week as part of the high-level international push to resolve the crisis.
Ahead of her visit, Ms Truss said: “The UK is determined to stand up for freedom and democracy in Ukraine.
“I’m visiting Moscow to urge Russia to pursue a diplomatic solution and make clear that another Russian invasion of a sovereign state would bring massive consequences for all involved.
“Russia should be in no doubt about the strength of our response. We have said many times that any further invasion would incur severe costs, including through a co-ordinated package of sanctions.
“Russia has a choice here. We strongly encourage them to engage, de-escalate and choose the path of diplomacy.”
The UK is prepared to impose what Ms Truss has branded “the toughest sanctions regime against Russia we have ever had” if there is an invasion of Ukraine, targeting those closest to the Kremlin.
Mr Johnson’s trip to Poland was confirmed by the foreign ministry in Warsaw, Reuters reported.
He will visit British troops stationed in the country.
It follows his talks with Lithuania’s Ingrida Simonyte in Downing Street and a call with Dutch Prime Minister Mark Rutte on Tuesday.
Russia has insisted it has no plans to invade Ukraine but President Vladimir Putin has raised concerns about Nato expansion in eastern Europe – Ukraine is not a member of the alliance but has received support from the West.
