* Saudi rejected council seat in protest at body's failure
* Jordan withdrew from rights council race against Saudi
* Jordan needs two-thirds U.N. General Assembly approval
Saudi Arabia officially notified the United Nations on Tuesday of its decision to reject a seat on the U.N. Security Council, which U.N. diplomats said clears the way for the likely election of Jordan as a replacement.
The 193-member U.N. General Assembly elected Saudi Arabia last month for a two-year council term from Jan. 1 but, in a surprise move, Riyadh declined the position a day after the vote in protest of the council's failure to end the Syria war and act on other Middle East issues.
Western diplomats, speaking on condition of anonymity, said on Friday it appeared Jordan had agreed to replace Saudi Arabia on the council after dropping out of a race against Riyadh for a seat on the U.N. Human Rights Council.
Jordan's place on the Security Council still would need to be approved by two-thirds of the General Assembly. Saudi's official letter on Tuesday to U.N. Secretary-General Ban Ki-moon allows for a new election to be called.
"I wish to inform you that the government of the Kingdom of Saudi Arabia has decided to advise you that Saudi Arabia will regrettably not be in position to assume its seat in the Security Council to which it was elected," Saudi Arabia's U.N. ambassador, Abdullah al-Mouallimi, wrote.
He attached to the short letter a copy of a Saudi Foreign Ministry statement that was issued a day after the Security Council election last month and outlines Saudi's decision to decline the seat.
Saudi Arabia, Cuba, China and Russia on Tuesday won three-year seats on the Geneva-based Human Rights Council, the United Nations' top rights body, despite concerns about abuses and restrictions on freedoms in all four nations.
Mouallimi called on Friday for "profound and comprehensive" reform of the U.N. Security Council that includes expanding its membership and "abandoning the veto system or restricting its use."
"The Security Council has failed to address the situation in the Palestinian and Arab occupied territories, an issue under consideration by the council for more than six decades," Mouallimi told a General Assembly debate on council reform.
"The Syrian crisis continues, with a regime bent on suppressing the will of its people by brutal force, killing and displacing millions of people under the watch and sight of a council paralyzed by the abuse of the veto system," he said.
Syrian ally Russia, backed by China, has vetoed three council resolutions since October 2011 that would have condemned Syrian President Bashar al-Assad's government and threatened it with sanctions.
Saudi Arabia has warned of a shift away from the United States in part over what it sees as Washington's failure to take action against Assad and its policies on Iran.
U.S. Secretary of State John Kerry met King Abdullah of Saudi Arabia last week and praised the U.S. alliance with Saudi Arabia as strategic and enduring but strains in the nearly 70-year-old relationship were apparent.