t would be "foolish" if Britain's main parties did not worry about Ukip topping a national election in Britain, former prime minister Tony Blair said.
Blair made no mention of Labour's performance or the response of Ed Miliband to the results in remarks to Swedish television reported by his office.
But he said: "Of course we should be worried when a party like Ukip comes first in the European election, it would be foolish not to be. But on the other hand we also have to stand for what is correct and right for the future of Britain in the 21st century.
Tony Blair would not comment on Labour's performance in the elections
"When the world is changing so fast, to end up having the debate dominated by anti-immigrant feeling and a desire to get Britain out of Europe, these are not solutions for the 21st century. They might be expressions of anger about what is happening in the world but they are not answers to what is happening in the world.
"Of course we have to respond in Europe as a whole on these issues but we have also got to have the courage and the leadership to stand up and take these people on. And in the end it's an ideology and philosophy that has nothing to offer people".
Blair said there was a "major issue" about the way Europe worked and said pro-Europeans had to take on board the message sent by voters.
He added: "At the same time we have got to be strong enough to show the leadership, to take on this wave of anti-immigration and old-fashioned ultra-nationalist feeling which isn't the future, has nothing to offer people and is no real response to the challenges of the 21st century.
"So it's a balance, it's a balance in which we need both the courage to reform and the courage to lead."
The current Labour leader Ed Miliband has insisted Labour will not guarantee an in-out referendum on EU membership despite being handed a drubbing at the polls by Ukip.
Miliband admitted the victory for Nigel Farage's party showed there was a "desire for Europe to work better for Britain" among the public.
But he stressed Labour had already set out its position on the referendum issue and would only back a national vote if a further transfer of powers to Brussels was being proposed.
Despite a strong performance in London, Labour lagged behind Ukip in the European parliament poll and only just managed to beat the Tories into third place.
They also failed to take control of local councils in key areas such as Essex and Swindon.
Miliband said the results showed Labour was making "progress", although there was "further to go".