SYDNEY (REUTERS) - Australian Prime Minister Malcolm Turnbull announced on Monday (Jan 18) a small increase in the Australian troop commitment to the Nato-led force supporting the Afghan central government during a surprise visit to Kabul.

Australia, which lost 41 soldiers in Afghanistan during its more than 12-year involvement in the conflict following the US-led invasion in 2001, will commit 20 more personnel to the mission, bringing its total to 270.

Mr Turnbull, speaking at the Australian Embassy in Kabul, defended the decision despite rejecting a request last week from US President Barack Obama to commit more Australian forces to the fight against Islamic State in Iraq and Syria (ISIS) militants.

"The truth is that in 2016, nowhere is a long way from anywhere. The world is so connected, more than it has ever been before. It is absolutely critical that we recognise that security is a global issue," he said.

Mr Turnbull, who deposed Mr Tony Abbott as leader in a party coup last year, has been a less vocal critic of the danger posed by Islamist militants than his predecessor, who continues to advocate a more forceful foreign policy.

Afghanistan, Pakistan, China and the United States are set to hold talks on Monday aimed at laying the ground for a negotiated end to almost 15 years of war between US-supported government forces and Taleban insurgents.

Taleban forces have stepped up their campaign in the past year to topple the Kabul government, which has struggled since most foreign troops left at the end of 2014. High-profile suicide attacks and Taleban territorial gains in Helmand province have underlined how far Afghanistan remains from peace.

The Taleban, which now control or contest more territory than at any time since they were ousted from power, will not attend the talks.

Mr Turnbull is set to visit Washington on Monday and Tuesday for a meeting with Mr Obama, where national security in the Middle East and Asia-Pacific regions are set to be agenda-topping items.