MPs will leave the Commons for almost three weeks today despite the looming international crisis in Ukraine, provoking warnings Parliament could be "left behind".
At around 7pm, Leader of the Lords, Lord Hill, will read a message from the Queen, sparking a constitutional procedure involving tricorn hats and Norman French, proroguing Parliament until the State Opening on June 4.
The event will close Parliament and unlike a normal recess, recalling MPs in the event of an emergency is very difficult and would require a Royal Warrant.
Labour MP John Mann said there were many subjects which could be discussed to fill the time - and warned MPs could very well need to be brought back to Westminster to debate Ukraine.
He said: "It's a volatile situation (in Ukraine). We don't want to be left behind."
David Cameron has announced the UK will face two extra Typhoon aircraft to help bolster Nato forces in the Baltic states.
The Prime Minister told Parliament's Liaison Committee the Government was also working on "a range of packages to help give planning and support and other advice to Nato allies"
The Ukrainian Defence Ministry says six of its soldiers have been killed and eight wounded in an ambush by pro-Russian separatists near the eastern city of Kramatorsk.
Russia will ban the United States from using Russian-made rocket engines for military launches, Deputy Prime Minister Dmitry Rogozin has announced.
The move comes in response to high-tech sanctions slapped on Moscow by Washington over Ukraine.
Rogozin also told reporters Russia would defy a US request and not prolong the use of the International Space Station beyond 2020.
"Many more" individuals and entities could be hit by sanctions over the Ukraine crisis after the criteria for punishments was widened, William Hague said today.
Speaking in the House of Commons, the Foreign Secretary also said that this weekend's referendum polls in eastern Ukraine were marked by "blatant fraud".
The European Union has imposed more sanctions against individuals linked to the Russian government, along with two Crimean companies.
Among the 13 individuals targeted are Vladimir Putin's first deputy chief of staff, Vyacheslav Volodin and the commander of Russia's paratroopers, Vladimir Shamanov.
Both men now face possible asset freezes and visa bans as the EU looks to pressurise the Kremlin over its handling of the crisis in Ukraine.
Russia's Foreign Minister Sergei Lavrov has said the European Union should respect the results of the referendums in the Donetsk and Lugansk regions of Ukraine over the weekend.
Mr Lavrov's comments follow an apparently overwhelming victory for pro-Russian separatists, with rebel leaders claiming over 85% of voters in both regions voted in favour of independence from Ukraine.
The leader of the rebels in Donetsk has now reportedly asked for his region to be incorporated into the Russian Federation, though the Kremlin has yet to respond to the request.
The self-declared 'mayor' of the rebel-held eastern Ukrainian town of Slaviansk has reportedly called for the Kremlin to send Russian troops into the region to help "provide stability".
The declaration from Vyacheslav Ponomaryov follows recent clashes in Slaviansk and other Ukrainian towns between pro-Russian separatists and Ukrainian government forces.
Pro-Russian separatists have declared independence for the south-eastern Ukrainian region of Lugansk, the Associated Press reports.
The move follows a referendum over the weekend that rebels say received the backing of over 90% of voters in Lugansk.
Earlier separatist leaders in Donetsk revealed they had asked the Kremlin to absord their region into the Russian Federation.