KUALA  LUMPUR: Malaysian Prime Minister Najib Razak called on world leaders to confront Islamist extremism, saying its "barbaric acts" do not represent any race or religion, as he opened a regional summit overshadowed by a spate of attacks around the globe.

Islamist militants killed 19 people in an attack on a hotel in Mali on Friday before Malian commandos stormed the building and rescued 170 people, many of them foreigners. This came a week after Islamic State militants killed 129 people in coordinated attacks in Paris.

"The perpetrators of these cowardly and barbaric acts do not represent any race, religion or creed, nor should we allow them to claim to do so," Najib said in his opening speech at the ASEAN summit.

"They are terrorists and should be confronted as such, with the full force of the law."

Malaysia has deployed extraordinary security measures around Kuala Lumpur as leaders from 18 countries, including US President Barack Obama, arrived for a pair of weekend summits.

Obama said on Saturday the Mali hotel attacks only stiffened the resolve of the United States and its allies, which would be relentless in fighting those targeting its citizens and would allow militants no safe haven.

"With allies and partners, the United States will be relentless to those who target our citizens," Obama said in opening remarks to ASEAN business executives. "We will continue to root out terrorist networks. We will not allow these killers to have a safe haven."

ECONOMIC COMMUNITY

Most of the leaders arrived from the Asia-Pacific Economic Cooperation (APEC) summit in Manila. Both the APEC meeting and the ASEAN summit typically focus on economic issues but have been overshadowed by the terrorist attacks.

Najib said he had intended to open the summit to talk about an economic community that the 10-nation Association of South East Asian Nations intends to launch in a region of 622 million people with a combined economic output of $2.5 trillion.

"But the events of recent days and weeks have cast a shadow over us all," he said.

He said predominantly Islamic countries such as Malaysia have a duty to expose as lies the "ideology propagated by these extremists that is the cause of this sadistic violence.

Malaysia has announced it is setting up a "counter-terrrorism" messaging center using social media and other messaging tools.

TENSIONS AT SEA

In a veiled swipe at China, which is also attending the meetings in Malaysia, Obama told the ASEAN business executives the United States was working with Southeast Asian allies to preserve maritime security and freedom of navigation.

"The United States is working ... to uphold the freedom of navigation and ensure disputes in the region are resolved peacefully," he said.

Beijing has overlapping claims with Vietnam, the Philippines, Malaysia, Taiwan and Brunei in the South China Sea, through which $5 trillion in ship-borne trade passes every year.

China has been transforming seven reefs in the Spratly archipelago into artificial islands and building three airfields and other facilities on some of them, prompting concern in Washington and the region that China is extending its military reach deep into maritime Southeast Asia.

China has said it does not want the South China Sea issue to be the focus of the meetings in Kuala Lumpur.

Obama said his signature free trade agreement, known as the Trans-Pacific Partnership (TPP), will bind the United States even closer to some of our strongest allies in Asia".

"Our alliances are the foundation for our security which becomes the foundation for our prosperity, which allows us to invest in the source of our strength, including our alliances," he told the ASEAN business executives.

The Asia-Pacific countries in the TPP include Japan, Singapore, Malaysia, Vietnam, Brunei, New Zealand and

Australia, all of whom are attending the Malaysia meetings.

GLOBAL REFUGEE CRISIS

After his speech, Obama visited a Kuala Lumpur educational center for refugees, many of them Rohingyas from Myanmar, to help focus attention, he said, on "an unprecedented number of refugees" across the world.

Speaking of the children he met, he said "that's the face of not only of children from Myanmar, that's the face of Syrian children and Iraqi children."

Alluding to Republican critics who are trying to block the flow of Syrian refugees to the United States, he said: "The notion that somehow we would be fearful of them, that the politics would somehow lead us to turn our sights away from their plight" was not in keeping with American values.