David Cameron and   Najib Razak
British Prime Minister David Cameron (R) pictured with Malaysian Prime Minister Najib Razak. Reuters

UK Prime Minister David Cameron embarks on South East Asian trip next week, calling for closer cooperation in fighting terrorism.

Ahead of his visit Cameron said in a BBC report: "Isil [Islamic State] is one of the biggest threats our world has faced.

"Britain can offer expertise on practical counter-terrorism work – dealing with the threat from foreign fighters and investigating potential terrorist plots.

"We will only defeat these brutal terrorists if we take action at home, overseas and online and if we unite with countries around the world against this common enemy.

"Last Monday, I set out what more we need to do at home to tackle this extremist ideology and build a stronger, more cohesive society.

"This week, I'll be talking to leaders in South East Asia about what they're doing to keep their country safe from these Islamist extremists.

"All of us face a threat from foreign fighters and from increasing radicalisation within our countries and it's right that we look at what help we can provide to one another.

"I think Britain can offer expertise on practical counter-terrorism work – dealing with the threat from foreign fighters and investigating potential terrorist plots.

"And I think Britain can learn from Indonesia and Malaysia on the work they have done to tackle the extremist ideology and to build tolerant and resilient societies."

Cameron will meet with Indonesian president Joko Widodo in Jakarta and Malaysian Prime Minister Najib Razak.

Around 500 people from Indonesia (which has the world's largest Muslim population) and 200 from Malaysia are thought have travelled to Syria and Iraq to join Isis militants.

Earlier this month, Malaysian police arrested two local men, believed to be linked to IS over suspected plots to attack several key areas, including the Klang Valley, a popular tourist haunt.

There were 154 Malaysian members of IS as of 7 May this year, according to Malay Online.

The four-day trip is mainly intended to boost trade with the UK, according to the BBC. However, Malaysian opposition lawmakers have called into question Cameron's visit amid the controversy surrounding 1Malaysia Development Berhad (1MDB), a state-owned fund which is under investigation for corruption allegations involving Malaysian Prime Minister Najib.

In a Financial Times report, Nurul Izzah Anwar, vice-president of the People's Justice Party (PKR) said she feared Cameron's visit would "send a negative perception" that the UK government was not concerned about "the current scandal-ridden ground on which Najib treads".