COPENHAGEN, April 1, 2008 (AFP) - US Defence Secretary Robert Gates said Tuesday he was 'reasonably optimistic' NATO would send reinforcements to southern Afghanistan but they would not be 'anywhere near' the commander's requirements.

Danish Defence Minister Soeren Gade, meanwhile, said Danish forces would stay in southern Afghanistan despite rising casualties.

The killing of a Danish soldier in Afghan fighting Monday raised the Danish combat death toll for the conflict to 14, most of them in the past year amid a resurgence of Taliban fighting.

'Every one of these casualties is a tragedy but it is for a greater cause -- security in Europe, security in America as well as helping the Afghan people to develop their country,' Gates told journalists in Denmark.

'There are a handful of us that are carrying the burden. Denmark is clearly one of the most significant ones, along with Canada, Australia, the British and ourselves.'

The Danish daily Politiken published photographs of the dead, underscoring the rising cost of the Afghan conflict to Denmark, which officials said has the highest per capita death toll of any of the allies.

The Danish defence minister said his country's troops had faced tough fighting and acknowledged that the losses had been painful.

But he said, 'We have no plans whatsoever to withdraw or something like that.'

The United States and allies with troops in the south have been pressing for other countries to contribute more forces and equipment to fill a shortfall experienced by the 43,000-strong NATO-led International Security Assistance Force.

The issue is at the top of the agenda of a NATO summit April 2-4 in Bucharest.

'I am reasonably optimistic that there will be more soldiers available for RC-South,' Gates said, using the military's designation for the southern Afghan sector.

NATO's minimum requirement is for two maneuver battalions and a border security battalion for ISAF, but the commander of the force, General Dan McNeil, has said he needs two combat brigades and a brigade of trainers -- about 10,000 troops.

The United States is sending 3,500 marines for a seven month tour to meet part of the requirement.

'I don't think we'll be anywhere near that number,' Gates said.