The move comes more than a year after Haitian legislators tried to change the old constitution to allow for dual nationality, which has long held up questions of land ownership and bids for public office. President Michel Martelly revoked that change just before it became official by being published in the National Gazette.
It is unclear why Martelly halted the earlier effort to allow Haitians dual nationality, but he is now switching course because of international pressure.
An estimated 2 million Haitians living in the United States, Canada and elsewhere have long wanted a greater say in the political affairs of their homeland.
"The matter of the dual nationality that was creating division between the diaspora and people here in Haiti, that's been resolved," Martelly told reporters at the National Palace as diplomats and lawmakers looked on. "All Haitians are Haitians."
The newly published constitution brought a mixture of surprise and hope to one Haitian leader outside of the country, Marleine Bastien.
"I think it was way overdue," Bastien, the founder and executive director of Haitian Women of Miami, said by telephone. "It shows that (Martelly) understands the great positive impact that the diaspora can play in the future of Haiti.
Haitians living abroad contribute 25 percent of the country's gross domestic product with remittances sent to relatives back home to a struggling country heavily dependent upon international aid.
Martelly on Tuesday also announced that a woman was named director to a newly formed election panel as part of a requirement that ensures 30 percent of government employees be women but didn't name her. The eight other members have yet to be named.
The new electoral council that was also created by the amended constitution is to oversee elections to fill the seats of 10 senators whose terms expired in May after a vote wasn't held in time. It's unclear when the government will organize elections for the empty senate seats, as well as mayoral posts.
The formation of the new electoral panel comes after last week's arrest of six former election officials on charges of misappropriating government property that included laptops and memory cards.
Martelly fired all nine members of the electoral council in December, and ordered them to return any government property still in their possession.
Members of the earlier council, appointed by former President Rene Preval, oversaw an election that was so marred with fraud and irregularities that it almost cost Martelly the presidency.
The next elections will be critical to the Martelly administration as it tries to encourage reconstruction efforts following a devastating 2010 earthquake. Martelly has few supporters in either house of Parliament, and his first year in office was marked by sparring with legislators.