Turkish Prime Minister Recep Tayyip Erdogan on Thursday voiced his country's unwavering support for Tehran's nuclear ambitions in a meeting with Iran's President Mahmoud Ahmadinejad, according to an official statement.

"The government and nation of Turkey has always clearly supported the nuclear positions of the Islamic republic of Iran, and will continue to firmly follow the same policy in the future," Erdogan was quoted as saying in the statement issued by Ahmadinejad's office.

U.S. President Barack Obama and Pakistan's Prime Minister Yousuf Raza Gilani vowed Tuesday to rescue a troubled anti-terror alliance which almost ruptured over 10 months of mistrust and recriminations.

The leaders met on the sidelines of a nuclear security summit in Seoul, in the highest-level exchange between the two sides since the killing of Osama bin Laden in a clandestine U.S. raid on Pakistani soil last May chilled ties.

World leaders called Tuesday for strong action to combat the threat of nuclear terrorism, including minimizing civilian use of highly enriched uranium (HEU), which can be turned into bombs.

"Nuclear terrorism continues to be one of the most challenging threats to international security," said a joint communique at the end of a two-day summit in South Korea bringing together leaders or top officials from 53 nations.

North Korea pushed back Tuesday at President Barack Obama's criticism of its plans to launch a satellite aboard a rocket, calling his stance confrontational and vowing to go forward with what it insisted was a peaceful mission.

Worries about the North's plans, which Washington and Seoul say are a cover to test long-range missile technology for a possible nuclear weapons program, have overshadowed a two-day nuclear security summit in Seoul that has drawn nearly 60 leaders.

World leaders including U.S. President Barack Obama on Monday began a two-day summit in South Korea aimed at curbing the threat of nuclear terrorism, organizers said.

The leaders or top officials from 53 countries, plus Interpol and three other international organizations, officially began the event with a working dinner hosted by South Korean President Lee Myung-Bak.

U.S. President Barack Obama met his Chinese counterpart Monday for talks expected to focus on North Korea's upcoming rocket launch, a day after a blunt appeal to Beijing to get tougher with Pyongyang.

Obama and President Hu Jintao held talks before the start of a nuclear terrorism summit in South Korea which has been overshadowed by the North's planned launch in mid-April.

U.S. President Barack Obama said he and Russian counterpart Dmitry Medvedev agreed Monday to support diplomatic efforts to end the bloodshed in Syria and ensure a "legitimate" government there.

Syria was one of the top priority issues discussed during a 90-minute meeting between the two leaders in South Korea ahead of a nuclear summit, their final direct talks before Medvedev steps down and makes way for Vladimir Putin.

South Korea is preparing to shoot down a North Korean rocket if it strays into the South's territory during a launch planned for next month, the defense ministry said Monday.

The South Korean and U.S. military are closely monitoring activity at the Tongchang-ri base, a ministry spokesman said, a day after Seoul confirmed the main body of a rocket had been moved to the site in the North's northwest.

U.S. President Barack Obama and Turkish Prime Minister Recep Tayyip Erdogan agreed Sunday on the need to send "non-lethal" aid to Syrian rebels, including communications equipment, a U.S. official said.

The two leaders agreed that a "Friends of Syria" group meeting on April 1 should seek to provide such aid and also medical supplies, as they met in South Korea on the eve of a nuclear security summit, said U.S. deputy national security adviser Ben Rhodes.

U.S. President Barack Obama warned North Korea Sunday that its "bad behavior" would be thwarted and the country would only deepen its isolation if it carried out a planned rocket launch.

"North Korea will achieve nothing by threats or by provocations," Obama said in a joint news conference with South Korean President Lee Myung-Bak on the eve of a nuclear security summit in Seoul.