LONDON — Britain's political establishment accused the leader of the country's anti-EU party on Thursday of being an apologist for Russia and its seizure of Crimea, going on the offensive after he bettered the deputy prime minister in a debate on Europe.

Nigel Farage, the head of Britain's UK Independence Party (UKIP), lambasted the European Union over its handling of Ukraine in the debate on Wednesday evening, saying the bloc had provoked Russia into taking action and had "blood on its hands".

"We should hang our heads in shame," Farage, whose party is forecast to poll strongly in elections to the European Parliament in May, said during an LBC radio debate with Nick Clegg, Britain's deputy prime minister.

"We have given a false series of hopes to a group of people in the western Ukraine and so geed up were they that they actually toppled their own elected leader. That provoked (Russian President Vladimir) Putin and I think the European Union, frankly, does have blood on its hands in the Ukraine".

All three of Britain's mainstream political parties have been rattled by UKIP's success in local elections and in opinion polls ahead of European elections in May and a national election in 2015, though UKIP has no seats in the British parliament.

Farage, whose party has nine seats in the European Parliament, was deemed to have bettered Clegg in the debate on Britain's future in Europe, by 57 percent to 36 percent, according to a YouGov poll for The Sun newspaper.

UKIP wants Britain to leave the EU, opposes "open door" immigration, and has spoken out against London being sucked into what it regards as ill-judged foreign wars. It is one of a number of euroskeptic parties across the EU that have blamed Brussels rather than Putin for Crimea's fate.

Russia moved into Crimea after Ukraine's Moscow-backed leader Viktor Yanukovych was overthrown on Feb. 22 following months of street protests against his refusal to sign a pact on closer ties with the EU.

Britain's political establishment united to condemn Farage.

Clegg said Farage's accusations against the EU over Ukraine were "perverse".

"It shows quite how extreme people can be like Nigel Farage when their loathing of the European Union becomes so all-consuming that they even end up siding with Vladimir Putin in order to make their point."

Paddy Ashdown, a former leader of Clegg's Liberal Democrat party, which is in a two-party coalition with Prime Minister David Cameron's Conservatives, said Farage's words were "extremely dangerous".

"His argument can only give comfort to Mr Putin's view of the world in the middle of an international crisis and provide excuses for him in the face of what is by any standards an egregious breach of international law."

Andrew Lansley, a Conservative member of Cameron's cabinet, demanded Farage withdraw his comments.

"I think it's outrageous that UKIP should be behaving as apologists for President Putin," Lansley told parliament.

When asked about Farage's comments, a spokesman for Cameron said the prime minister was convinced that responsibility for the Ukraine crisis lay with Russia and its Crimean supporters.

It is unclear whether UKIP's sympathy for Russia will help or harm it at the polls in May. Such elections rarely turn on foreign policy, and protest parties tend to score best on the kind of low turnout widely expected in this vote.

UKIP said it made no apologies.

"UKIP was the first party to oppose Western intervention in Syria," Patrick O'Flynn, a party spokesman, said on Thursday.

"We're delighted to call out the EU for crass mishandling of the Ukraine crisis too".