Kerry in Southeast Asia seeking support against Islamic State

Kerry is among foreign dignitaries visiting Jakarta for the inauguration of Widodo, a former furniture exporter who is the first leader of the world's third-biggest democracy to come from outside the political and military elites.

During his one-day visit, the United States' top diplomat will use a series of bilateral meetings to urge Widodo, known by his nickname Jokowi, and other Southeast Asian leaders to take more action against the growing threat from IS, officials said.

During the meetings, "I would put at the top of the list the international effort to degrade and ultimately destroy ISIL," said a senior state department official, using an alternative name to refer to the group.

"Breaking it down, the effort to combat violent extremism, to block recruitment, and to protect against the solicitation of foreign fighters," the official added.

"To guard against the return of hardened fighters to the region, debunking and denigrating extremist propaganda, blocking illicit terrorist financing"

As well as Widodo, Kerry is due to meet with Malaysian Prime Minister Najib Razak, Singaporean Prime Minister Lee Hsien Loong, the sultan of Brunei and Philippine Foreign Secretary Albert del Rosario.

IS's fighters appeal is fanning fears that it could serve as a potent new rallying cry for extremists in the region who had been largely brought to heel following deadly attacks.

There is particular concern about Indonesia, the world's most populous Muslim-majority country, and neighbouring Malaysia.

Authorities in those countries have watched with alarm as scores, possibly even hundreds, of their nationals are believed to have gone to Syria and Iraq to join the fight for a hardline Muslim caliphate.

Malaysian police have arrested a total of three dozen people this year for suspected IS-related activities.

Jakarta has sought to ban support for IS ideology while police believe up to five Indonesians -- including two suicide bombers -- have died fighting with radical groups in the Middle East this year.

Indonesia launched a crackdown on extremists a decade ago after a series of attacks on Western targets, which has been credited with weakening key militant networks.

During his meetings, Kerry will press Southeast Asian countries on areas "where we believe and hope that the individual countries can do more", the State Department official said.

Territorial disputes in the South China Sea, climate change and the Ebola virus will also be on the agenda during the meetings, officials said.