The bombings in Madrid may have broken Spain's heart but they have not crushed its spirit, the deputy prime minister has told Labour delegates.
John Prescott said he was moved by what he saw in Spain
John Prescott, who represented Britain at Madrid's anti-terror rally, told the spring party conference no city on earth was now safe from the terrorists.
He said such extremism knew no limits but countries could combat terror by standing together.
He also urged an end to feuding among Labour MPs as local elections approach.
Mr Prescott said of his visit on Friday to Madrid: "I was moved by the scale of the protest."
He said the voices of the millions of people who took part had been heard around the world.
"I was proud to link arms with leaders from around Europe and with people from all over Spain.
"In their grief and anger we stand with them.
"Their fight is our fight too. Barbaric terrorism recognises no national boundary. Extremism, by its nature, knows no limit," he said.
He said the spirit of "defiance" in the face of terrorism was evident as the Spanish went to the polls on Sunday.
'Leaders of courage'
"The voters of that country choose to exercise their democratic rights in a general election and by doing so defy the terrorists," he said.
"And so the ballot box is ultimately more powerful than the bomb or the bullet - and in that we offer them our solidarity."
He drew a link between the bombings in Spain's capital and the terrorist attack eight years ago in Manchester, the city hosting this year's spring conference.
He said: "They chose Madrid but no city on earth is safe. The people of Manchester know that.
"The reality of terror explains the heavy security around this conference."
He praised Manchester's recovery since its terrorist attack and said he had seen the same spirit on the streets of Madrid.
Mr Prescott said "leaders of courage" like Tony Blair were what countries needed to face the "risks and challenges" of the modern world.
He called on Labour Party members to stop any feuding among MPs as the party prepared for crucial local council and European elections.
The deputy prime minister warned delegates the Tories were stronger now than they had been for years and could capitalise on any lack of Labour discipline.
He acknowledged the government could do more, but said: "I support my Labour government, on principle.
"Let's be the first generation of Labour people who refused to tear themselves apart and by default saddle the British people with yet another Tory government."
Mr Prescott praised Labour councils for bringing down council tax rises this year but warned delegates: "Let's be under no illusions.
The Tories are stronger now than they were under Iain Duncan Smith, they've got a spring in their step. They'll be fighting us in every seat."