HAVANA - (AP) -- With cries of ''Viva Fidel!'' and ''Homeland or Death!'' lawmaker after lawmaker argued Tuesday in favor of enshrining socialism in Cuba's national constitution as a permanent act of defiance and political self-preservation amid growing demands for democratic reforms.

  Well into the second day of a special session called by President Fidel Castro, National Assembly members left no doubt that they later would approve the government proposal to make Cuba's economic and political systems sacrosanct.

  ''I vote for my perfectible, socialist nation,'' said lawmaker and world-renowned folk singer Silvio Rodríguez.

  Foreign Minister Felipé Pérez Roque, another National Assembly member, said the amendment would protect the socialist system and the ruling Communist Party of Cuba for future generations after the deaths of Castro, 75, and his brother and designated successor, Raúl Castro, 71.

  The amendment is ''key,'' said Pérez Roque, to ``what we do when the generation that carried out the revolution, and the command of today, the generation of Fidel, of  Raúl . . . is no longer with us.''

  ''What we do today expresses our hope for the future,'' Pérez Roque added. ``This is a guarantee of the future, that we preserve our authority as a party.''

  The constitutional change is being discussed as Cuba comes under new pressure from at home and abroad to carry out democratic reforms.

  As the speeches continued into a second evening on Tuesday, National Assembly President Ricardo Alarcón announced that the session -- and a nationwide work
  stoppage -- would continue into a third day today. The government has closed banks and schools and most offices, factories and stores so that citizens can follow the sessions, which are being broadcast on state television.

  The government says the proposed amendment is its answer to President Bush's refusal last month to lift American trade and travel restrictions until Cuba undertakes reforms, including multiparty elections.

  But the measure also appears to be Castro's effort to undermine the Varela Project, a homegrown effort to organize a referendum on the question of reform, said
  opposition activists and Latin America specialists.