Nelson Mandela at a party for his 90th birthday in London last Friday: The U.S. used to maintain that his African National Congress was a terrorist group with Communist ties. (Lefteris Pitarakis/Associated Press)

Nelson Mandela's name has been removed from the U.S. terrorism watch list, enabling the former South African president and Nobel Peace Prize winner to finally travel freely in the U.S.

U.S. President George W. Bush signed a bill Tuesday that pulled Mandela and his African National Congress from the list, which has existed since Republican Ronald Reagan was president in the 1980s.

Republicans and Democrats alike have since spoken out against Mandela's inclusion on the list, with U.S. Secretary of State Condoleezza Rice calling it embarrassing and Senator John Kerry saying it was a great shame to dishonour Mandela in such a way.

The list meant Mandela, who turns 90 later this month, could not technically visit the U.S. without the secretary of state certifying that he is not a terrorist.

During the Cold War, the U.S. accused the African National Congress of being an organization with Communist ties that was using militant tactics to bring down pro-Western South Africa.

Mandela and the congress fought apartheid in South Africa for decades. Mandela's efforts landed him in prison for 27 years, until his release in 1990. Apartheid fell soon after and Mandela was elected South Africa's first black president in 1994.

He retired from politics in 1999 and has since campaigned to prevent the spread of AIDS.

With files from the Associated Press