MONTEVIDEO, Nov 03, 2011 (AFP) - South America's biggest trading bloc Mercosur will sign a free trade pact with the Palestinian Authority at an upcoming annual summit in December, its Uruguayan presidency said Thursday.

The deal, initialed in Ramallah last month, will be formally signed in the presence of Palestinian president Mahmud Abbas at Mercosur's headquarters in the Uruguayan capital Montevideo, Foreign Minister Luis Almagro said.

"In principle, we will sign this deal on free trade with Palestine, and to this end we are inviting the president of the Palestinian state," Almagro, whose country holds Mercosur's rotating presidency, told journalists.

The Uruguayan foreign minister said negotiations on the free trade agreement, which began in December 2010, were "practically finished."

The members of Mercosur -- Argentina, Brazil, Paraguay and Uruguay, plus Venezuela, which is in the process of joining -- have already recognized Palestine as a state.

An FTA between Mercosur and Israel came into force in March 2011.

Argentina, Brazil, Paraguay and Uruguay formed Mercosur in 1991 with the aim of creating a South American common market. Venezuela signed a membership agreement in 2006 that awaits full ratification. Bolivia, Chile, Colombia, Ecuador and Peru are associate members.

News of the signing of the Mercosur deal comes amid a deepening rift between the Palestinians and the United States after the Palestinian Authority defied warnings to become a full member of the United Nations cultural body UNESCO.

Abbas had submitted a separate request for UN membership in September, and the UN Security Council is due to meet on November 11 to decide whether to hold a formal vote on the application.

As a permanent Security Council member, the United States says it will veto any resolution granting full UN membership to the Palestinians.

But the Palestinians insist they will seek membership in more world bodies despite stiff US and Israeli opposition.

US President Barack Obama says the Palestinian campaign is an unwelcome distraction from the tough bargaining needed with Israel to make real progress toward a two-state solution.

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