By Michael Conlon

 CHICAGO (Reuters) - Branding Fidel Castro a tyrant, White House national security chief
 Condoleezza Rice called on Monday for renewed international pressure against the Cuban
 leader.

 Speaking just days after President Bush said he would begin tight enforcement of an existing
 ban on travel by U.S. citizens to the island nation, Rice said Castro's crackdown on
 dissidents have brought him worldwide condemnation.

 "This needs to be an international effort," she told a meeting of the Inter American Press
 Association in Chicago. "It is unacceptable that Cuba remain in the state that it does in this
 hemisphere at a time when democracy and freedom and prosperity are within grasp ... it
 should not be that the Cuban people are forgotten."

 Cuba on Monday rejected the renewed pressure from Washington for reforms and said Bush
 was "dreaming" of a post-Castro transition.

 A Cuban Foreign Ministry statement in Havana said steps announced by Bush to hasten
 political change on the island were aimed at securing the votes of the Cuban exile community
 in Florida, the pivotal state in his controversial 2000 election.

 Speaking by a video connection from her Washington office, Rice told the Chicago meeting
 she could not predict when a stepped-up enforcement of travel restrictions would begin but "I
 can tell you that there is a process to begin immediately enforcing these ... restrictions as
 quickly and fully as possible."

 "We know there are a lot of people who are using the travel opportunities to go to Cuba in
 ways that wind up enriching the Cuban government because the Cubans are able to take the
 money in hard currency to then pay the workers in pesos and to pocket the difference ... it is
 simply unacceptable," she said.

 "We do not want to enrich the tyrannical government of Fidel Castro. We do not want to allow
 him to use these monies to fund his tyranny, his crackdown on dissidents," Rice said of the
 communist-run government.

 In response to a question about the future of Venezuela, where President Hugo Chavez is
 resisting efforts to call a referendum on his rule, Rice said "We are very supportive of the
 efforts of the Organization of American States in trying to oversee a process that will get
 Venezuela to a constitutional electoral process that will resolve these issues.

 "We do not see it as a bilateral issue ... but rather a regional issue and it should be treated as
 such," she said.

 At the same time, Rice said "We have our concerns about some of the activities of the
 Venezuelan government and we make those known to Venezuela on a regular basis."