Washington (CNN) -- The United States on Tuesday slapped travel sanctions on Ivory Coast President Laurent Gbagbo, as well as 30 members of his government, following a disputed presidential election in the West African country.
The move joins European Union sanctions against Gbagbo and is expected to pressure him to step down from office and leave the country, said Deputy Assistant Secretary for African Affairs William Fitzgerald.
The ban took effect immediately, Fitzgerald said, and could result in the deportation of family members of Gbagbo and his allies who may be studying in the United States.
He also warned of the potential for additional sanctions against Gbagbo's allies.
"The results are clear, and it's time for him to go," White House Press Secretary Robert Gibbs said of Gbagbo on Monday.
The country's Independent Electoral Commission said opposition candidate Alassane Ouattara won the November 28 presidential runoff, but the country's Constitutional Council invalidated those results and declared Gbagbo the winner.
Several world bodies, including the United Nations and African Union, have declared Ouattara as the winner.
The U.N. Security Council had joined several other international bodies in calling for Gbagbo to step down.
The Council on Monday extended its peacekeepers' mission in the West African country through June 30, despite an expulsion order days earlier by Gbagbo.
The peacekeepers' mission had been scheduled to end December 31.