Bush ordered additional funding for pro-democracy programmes in Cuba
Experts say the move is an attempt to avert criticism by Cuban-Americans of a decision expected next week suspending for a further six months the right of US firms to sue foreign companies doing business with expropriated properties in Cuba.
"Seven years ago today, a tugboat carrying 72 people off the coast of Cuba...was repeatedly rammed by Cuban authorities resulting in 41 deaths, including 10 children," Mr Bush said.
"The tyranny that rules Cuba today bears direct responsibility for this and other crimes - crimes, that should not go unpunished, against innocent civilians and countless other human rights violations over the years," he said.
Additional funding
Mr Bush said he had asked the Treasury Department to enhance and expand the sanction enforcement capabilities of the Office of Foreign Assets Control.
"It is important that we uphold and enforce the law to the fullest extent with a view toward preventing unlicensed and excessive travel, enforcing limits on remittances and ensuring humanitarian and cultural exchanges actually reach pro-democracy activists in Cuba," he said.
Mr Bush also ordered additional funding for non-governmental organisations to work on pro-democracy programmes in Cuba.
By Monday Mr Bush must decide whether he will extend a politically sensitive suspension of a provision in the 1996 Helms-Burton act that allows US citizens to sue anyone dealing in properties seized after Cuban leader Fidel Castro took power in 1959.
Undecided
Former President Bill Clinton suspended the legal provision every six months to avoid angering European nations and Canada who have business interests in Cuba.
This is the first time since he became president that Mr Bush has had to make the decision.
Mr Bush's National Security Adviser Condoleezza Rice said on Friday Mr Bush had not yet made up his mind on the waiver.
But analysts and government sources said Mr Bush was expected to suspend the provision, believing it was in the US national interest and was the best way to achieve democratic change in Cuba.