World leaders called Tuesday for a crackdown against terrorist groups and tougher steps to prevent the spread of weapons of mass destruction as they wrapped up an economic summit shrouded in security concerns and rattled by one and possibly two North Korean missile tests (search).

The 21-nation summit of Asia-Pacific Economic Cooperation (searchwas concluding two days of talks with a luncheon that officials said would be a freewheeling discussion about economic problems and security issues. Afterward, President Bush (searchwas heading from Bangkok to Singapore for an overnight stay and then quick visit to the Indonesian island of Bali where terrorist tensions were high.

The final communique was not expected to specifically mention North Korea's nuclear threat, although South Korea (searchwanted the subject to be addressed in the document. Leaders were considering whether to reference it outside the formal declaration.

The White House said it was not disappointed, saying the United States and other nations engaged in talks with North Korea were unanimous in calling for a nuclear-free peninsula.

"All five nations are speaking with one voice," presidential spokesman Scott McClellan said.

While some nations complained that security issues were dominating the meeting's stated economic agenda, the summit urged all countries to "eliminate the severe and growing danger problem posed by the proliferation of weapons of mass destruction," a senior administration official said, reading from the summit communique.

The leaders also urged countries to "dismantle fully and without delay transnational terrorist groups that threaten the APEC economies."

On the economic front, the leaders agreed to revive global trade (searchliberalization talks that collapsed recently in Mexico. They did not offer a formula to break the impasse but directed negotiators go back to work on the text they had left behind, the White House said.

China's president, Hu Jintao, urged summit partners to take a tough stand, and Australian Prime Minister John Howard, a close U.S. ally, said action was more important than words.

"For some time, terrorist attacks have gone on unabated in the Asia-Pacific region, undermining the economic and social development of a number of countries," Hu told the summit, according to the state-run Xinhua News Agency.

The leaders also were expected to urge tighter control on the production of weapons that can be used to shoot down commercial aircraft -- but stopped short of calling for an outright ban, according to a draft communique obtained by the Associated Press.

Before heading to their closing meeting, the leaders gathered in an ornate royal palace for a group photograph. Following a long-standing tradition, they wore shirts of the host country -- in this case, tailored Thai silk ones, featuring animal and floral patterns.

North Korea rattled nerves by firing an anti-ship missile off its east coast as part of its annual military exercise. It was North Korea's first missile test-firing since April and called attention to Bush's fledgling proposal to defuse tensions by offering Pyongyang a five-nation security guarantee if it would scrap its nuclear weapons program.

On Tuesday, Japan said it suspected that North Korea may have test-fired a second missile. The government said it was trying to confirm the information. A spokesman at the South Korean military's Office of Joint Chiefs of Staff disputed Tokyo's claim of a second test.

The United States pressed the summit to take note of Bush's initiative, which would commit the United States, China, Japan, Russia and South Korea to a no-invasion pledge.

The administration said its proposal was still in the early stages of development. A U.S. official in Washington said the administration was still debating issues such as when to offer a security pledge and what North Korea would have to do beforehand.

U.S. officials viewed North Korea's missile firing as a provocative attempt to get attention during the summit but said it only served to isolate the already reclusive regime. Bush met with South Korean President Roh Moo-hyun and they issued a joint statement urging North Korea "to refrain from any action which would exacerbate the situation."

The scourge of terrorism was a prominent summit topic, underscored by Indonesia's warning of possible attacks as Bush prepared to visit the island of Bali in a quick stop Wednesday en route to Australia. Bush personally thanked Thailand for the capture of Asia's top terror suspect, known as Hambali, who is accused of masterminding bomb attacks against U.S. and other Western targets across Southeast Asia.

Bush was leaving the summit Tuesday for a short overnight stay first in Singapore.

"The threat of terrorist attacks is imminent," Indonesian security minister Susilo Bambang Yudhoyono told a group of international business leaders, warning that Indonesia must remain vigilant despite the arrests of dozens of terror suspects. More than 200 people were killed in terrorist bombings on Bali a year ago.

In a plaintive appeal, Japanese Prime Minister Junichiro Koizumi asked leaders to take note of North Korea's abduction of Japanese citizens when addressing the nuclear crisis. He raised the matter with Russia, China and South Korea on the sidelines of the summit Monday.

"For Japan, the concern isn't only the nuclear issue, but also the abductions," he said. "It's a special issue for Japan, but it's also a human rights issue that cannot be ignored. I want to continue to urge the other leaders to understand our position and to help us." The kidnapping of Japanese during the 1970s and 1980s by North Korea to train its spies has been a major sticking point between the Asian neighbors.

Malaysian Prime Minister Mahathir Mohamad was among the leaders who complained that security issues were diverting attention from economic problems.

But leaders spent much of their day Monday discussing how to get the World Trade Organization to restart talks for a new global commerce deal following the collapse of negotiations last month in the Mexican resort of Cancun. Hoping to attract more investment capital for Asia's battered economy, the leaders also agreed to do more to combat corruption and to "promote transparency" in public financial management.

They also pledged to be better prepared for any future outbreaks of SARS, other infectious diseases or bioterrorist attacks, according to the communique draft.

In a private moment at the summit, Bush pulled aside Mahathir to object to his statement that Jews rule the world. McClellan said Bush told Mahathir his remarks were "wrong and divisive."

The move represented a further deterioration of relations between Kuala Lumpur and Washington, since Bush invited Mahathir to the White House in May 2002 and praised him as an ally in the war against terrorism.