CUBAN revolutionary leader Fidel Castro has cautiously welcomed the tentative improvement in relations with the United States — but warned Washington his country “has lasted decades without raising the white flag and never will.”

In a frank address to the student federation at the University of Havana, the former president said he “did not trust the policy of the United States, nor have I exchanged a word with them.

“But that doesn’t mean I reject a peaceful solution of conflict.

“We will always defend co-operation and friendship with all the peoples of the world, including our political adversaries,” he said.

But he reflected that when a student himself it was only through studying Marx that he “came to better understand the strange and complex world it has fallen to us all to live in.”

Students should take inspiration from Marx, Lenin and Mao Zedong, he said, to avoid the “bourgeois illusions whose tentacles manage to entangle the less experienced.

“Revolutionary ideas must always be on their guard as humanity multiplies its knowledge.”

Mr Castro said the prompt for better relations with the United States had been the now famous handshake between his brother, current Cuban President Raul Castro, and US President Barack Obama at the funeral of Nelson Mandela.

“The distinguished and exemplary fighter against apartheid was friendly with Obama,” he noted — a dramatic development considering US backing for apartheid South Africa at the time Cuban forces were battling the racist army in Angola.

Cubans should remember the lessons of that period — when “peace negotiations were excluded while Angola was attacked by the forces of apartheid.

“In such a situation there was no possibility of a peaceful solution.” Only determined resistance with military assistance from the Cubans “forced that arrogant country to negotiate a peace agreement that ended the military occupation of Angola and presaged the end of apartheid in South Africa.”

But if anything, the world was in a more lawless and violent state today.

“The serious dangers that threaten humanity should give way to rules that are consistent with human dignity,” Mr Castro said.