Maliki said he signed separate agreements to establish diplomatic relations with both countries Friday, a move that will lead to an exchange of ambassadors, the Palestinian Ma'an news agency reported.
"This recognition highlights the collective international approval of Palestinian rights. It is a new success for Palestinian diplomacy," he said.
Grenada and Haiti join more than 130 countries that officially recognize the State of Palestine, the agency said.
In 2012, the U.N. General Assembly approved a resolution that upgraded the Palestinian Authority's status recognizing it as a "member state."
Israel, Canada, the United States, Panama, Nauru, Palau, Micronesia and the Republic of Czechoslovakia voted against the resolution, the agency said.
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