OTTAWA — Canada and the Netherlands are expected to issue a joint plea to reluctant allies at this week's NATO summit, asking them to pare down the restrictions they've placed until now on their combat forces in Afghanistan.

The hope is that the pressure by Prime Minister Stephen Harper and Dutch Prime Minister Jan Peter Balkenende will have an impact across Europe, where a number of countries have been reluctant to allow their troops to take part in offensives against Taliban militants.

Nevertheless, the two leaders will likely be careful in the way they couch their remarks.

"It's not going to be aimed at a specific country,'' said a defence source who spoke on condition of anonymity. "Nobody wants any finger-pointing.''

 NATO leaders meet this week in Riga, Latvia where the struggling mission in Afghanistan is expected to top the agenda. A previous call by the alliance's commanders for an additional 2,500 troops, and for fewer national limitations on those already deployed, has been met mostly with silence so far.

In the backrooms of NATO, Germany has been under the most pressure to give its soldiers freer rein to patrol and fight where necessary, said a diplomatic source.

Canadian, American, British and Dutch forces in southern Afghanistan have been bearing the brunt of the heavy fighting and casualties against Taliban insurgents. Since 2002, 42 Canadian soldiers and one diplomat have been killed, mostly around Kandahar.

German, French and Italian forces patrol relatively quiet sectors in the north, east and west. They are also under extensive, self-imposed restrictions -- or national caveats -- that prohibit them from taking up combat operations. The Germans and Italians impose the strictest caveats, according to a recent U.S. Congressional research report.

A public plea for fewer limitations coming from Canada and the Dutch is seen as having a better chance of success in countries where opposition to the U.S.-led war in Iraq is still running high, said one government source.

 Another senior Canadian official, who spoke to reporters last week on background, said Canada has been active on the diplomatic front. "I think we've talked to all NATO countries involved in Afghanistan about the nature of their presence,'' said the official.

The national caveats have been a source of strain among the 26 NATO members serving in Afghanistan.

Some countries do not allow their forces to patrol more than 80 kilometres beyond their bases, eliminating the possibility of overnight operations for those soldiers. Others, who patrol the Kabul airport, are not allowed off the property.

The list of national caveats -- contained in a classified book -- is apparently as big as a city telephone directory.

Even though many NATO parliamentarians have voted to press their governments to ease restrictions, members of the German, French and Italian delegations balked. They all said they see their role in Afghanistan as one of rebuilding the country, not hunting down the Taliban.

Much of the insurgency is fuelled by organizations and bases on the Pakistani side of the Afghan border. Pervez Musharraf, Pakistan's president, has been accused of not aggressively cracking down on Taliban supporters.

 A proposal to have an exchange of liaison officers between NATO and Pakistan, especially in Pakistan's restive northern tribal regions, is also expected to be discussed at Riga. 

Aside from loosening troop restrictions, senior Canadian officials hope the summit will see progress in cajoling member countries to provide what are termed enabling elements -- helicopters, air transport and medical teams.

"Aid and development, assistance to police, there are all kinds of ways in which we can knit this together and contribute nationally, and particularly in the south (of Afghanistan),'' said one official.

For example, if other NATO members were willing to contribute to support functions, particularly the training of Afghan police and army units, it could in theory free up American, Canadian and British troops for combat.

Canada, with its current 2,500 combat troops, will not be increasing its commitment in that area.