NOORDWIJK, Netherlands — The mounting tension on Turkey’s border with Iraq and American demands for European allies to do more in Afghanistan are expected to dominate a meeting of NATO defense ministers opening today in the Netherlands.

Although not on the official agenda, the situation on Turkey’s southeastern frontier risks overshadowing the two-day gathering.

Turkey’s NATO allies have expressed solidarity following a surge in attacks by Kurdish rebels, but have also urged restraint as the Turks consider retaliatory attacks on Kurdish bases over the border in Iraq.

The NATO meeting comes amid intense diplomatic efforts to avert a Turkish offensive, which Western nations fear could destabilize one of the most stable parts of Iraq. Turkey yesterday rejected a rebel cease-fire offer and massed troops on the border with Iraq.

On Afghanistan, Defense Secretary Gates will push European allies to deploy more troops, putting the focus on military training teams that allied commanders see as vital to an eventual exit strategy for international forces.

Mr. Gates is also expected to seek helicopters, transport planes, and quick maneuver troops to fill shortfalls in NATO’s 40,000-strong Afghan force during the talks in the North Sea resort of Noordwijk.

Mr. Gates criticized some European members of NATO on Monday for failing to provide the extra troops that their governments promised last year for the force.

“I am not satisfied that an alliance whose members have over 2 million soldiers, sailors, marines and airmen cannot find the modest additional resources that have been committed for Afghanistan,” Mr. Gates said Monday during a visit to Ukraine.

As part of efforts to fill gaps, ministers will consider a plan to lease transport helicopters from private companies — possibly from Ukraine or Russia. To allay safety fears, diplomats say the leased aircraft would be used only to carry equipment and supplies, freeing up NATO’s military choppers to transport troops.

America wants allies to more than double the approximately 20 teams of embedded trainers serving with Afghan army units. NATO commanders say such teams are key to preparing local forces to gradually take over from international forces — although they believe it could be five to 10 years before Afghan troops can operate independently without American and NATO support.

Russia’s defense minister, Anatoly Serdyukov, will join the NATO talks tomorrow when differences over Kosovo and proposed American anti-missile bases in Eastern Europe are expected to loom large.