"Peace must come to the Holy Land," Barack Obama said Wednesday as he landed in Israel for the first time as U.S. president in a bid to ease tensions with his hosts and to frame policy on Syria and Iran.

Israeli leaders showered Obama with personal praise for defending the Jewish state's security and existence, in a lavish welcoming ceremony at Tel Aviv's Ben Gurion airport at the start of a three-day visit to Israel and the Palestinian territories.

Iran on Wednesday accused "armed opposition groups" in Syria of having used chemical weapons on the city of Aleppo, warning against a recurrence of such attacks, the official IRNA news agency reported.

"The Islamic republic of Iran strongly condemns the inhumane act by armed opposition groups in using chemical weapons in the city of Aleppo," foreign ministry spokesman Ramin Mehmanparast said.

Kuwait's parliament on Wednesday passed a bill to grant citizenship to up to 4,000 foreigners in 2013 in a move to resolve the problem of stateless people in the oil-rich state.

Forty-three members, including all cabinet ministers present, voted in favor of the law while only two MPs abstained without any opposition. To take effect, the law also must be signed by the emir.

Al-Qaida's Iraqi affiliate said it was behind a wave of attacks that killed 56 people and wounded more than 220, in a statement posted on jihadist Internet forums on Wednesday.

"What you received on Tuesday is... the first stage that, God willing, will be followed by revenge for those whom you executed," the statement said.

Turkey's armed Kurdish rebellion is poised to enter a historic ceasefire on Thursday, the Kurdish New Year, at the command of a single man only a handful of people have seen since 1999.

After months of meticulous planning with Turkey's intelligence agency, jailed rebel leader Abdullah Ocalan has outlined a "historic" call for a ceasefire to be made on Thursday, Kurdish lawmakers told reporters after meeting him on Monday.

U.N. Secretary General Ban Ki-moon remains convinced that the use of chemical weapons by any party in Syria would constitute an outrageous crime, the U.N. said Tuesday.

The comment came after Syria's government and opposing rebels on Tuesday each accused each other of using chemical weapons for the first time in two years of unrest in Syria.

The Saudi authorities have arrested 18 suspected spies, including an Iranian and a Lebanese, on charges of espionage for a foreign country, the interior ministry said on Tuesday.

"Sixteen Saudis, an Iranian and a Lebanese were arrested in coordinated and simultaneous operations in four regions of the kingdom," including the capital Riyadh and the holy city of Mecca, the ministry said in a statement.

The United States on Tuesday welcomed the election of a long-time Texas resident as the Syrian rebel prime minister, voicing hopes he can foster "unity and cohesion among the opposition”, as Russia expressed that it “deeply regrets” this step.

U.S. officials "know and respect" Ghassan Hitto from his work with the Syrian coalition on humanitarian efforts in Syria, State Department spokeswoman Victoria Nuland told reporters.

U.S. Secretary of State John Kerry arrived in Israel Tuesday and was expected to attend some meetings a day ahead of President Barack Obama's milestone visit, U.S. officials said.

"The secretary is in Israel, in advance of the president's arrival," State Department spokeswoman Victoria Nuland told reporters in Washington.

The daughter of Iran's former president Akbar Hashemi Rafsanjani was released Tuesday after serving a six-month sentence on charges of propaganda against the regime, her lawyer told the ISNA news agency.

Lawyer Sohrab Soleimani said Faezeh Hashemi, who was arrested in late September and taken to Tehran's notorious Evin prison, was released in the early hours of Tuesday, ISNA reported.