Seventy years ago they marched out of Barcelona for the last time, proud heroes who had risked their lives to fight General Franco's Fascist-backed rebels.

Yesterday, a small band of veterans of the International Brigades returned to mark the anniversary in Sitges, near Barcelona.

Frail, some in wheelchairs, they joined in a chorus of La Bandera Roja, or The Red Flag, an Italian song popular with anti-Fascist forces during the war.

Now the eight British and Irish survivors of the 2,300 men and women who joined the brigades are fighting a new battle against time to win an honour that has stayed out of their grasp: Spanish nationality.

Twelve years after first being offered citizenship for their contributions during the Spanish Civil War, they are yet to become Spaniards.

José Luis Rodríguez Zapatero, the Socialist Prime Minister, said this month that they would finally be awarded joint citizenship but no date has been set for them to receive the honour. All are now in their nineties or even over 100, and risk missing out for ever.

Sam Lesser, 93, from London, one of three British veterans who travelled to Sitges, said: “The sooner we get it, the better. The old man with the scythe marches on and we are not getting any younger.”

Veterans, including Bob Doyle, an Irish citizen, wrote to the Spanish Embassy in London asking when they might be given Spanish nationality but await a definite answer.

In 1996 Spain offered Spanish nationality to veterans of the International Brigades on condition that they gave up their own nationality. All refused.

Despite their age, most veterans retain vivid memories of the unsuccessful struggle to defend the Republic against General Franco's rebels, who won the war in 1939.

All volunteered because they felt the need to make a stand against the rise of Fascism across Europe. While Hitler and Mussolini sent arms and troops to help Franco, Britain and other countries stood aside.

“When we come back now Spaniards treat us very well,” said Mr Lesser. “But one girl said to me this week 'You fought for us but your country didn't'.”

To most of the veterans, modern Spain is barely recognisable. “They still used ploughs with horses, there were no tractors and it was like England in the Middle Ages,” said Jack Edwards, 94, from Telford, Shropshire.

But time has not dimmed their ideals. Jack Jones, 95, from London, who went on to lead the Transport and General Workers' Union, said: “We came to fight for freedom and democracy, things that we still believe in.”

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