The US defence secretary angered Nato allies in January after he publicly criticised European Nato forces in the country for not knowing how to fight a "guerrilla insurgency".
Gates welcomed a pledge by Italy to lift restrictions on the movement of its 2,350 soldiers, most stationed in western Afghanistan, but it remained unclear whether Rome would be willing to move them to a more hostile area.
"The Italians took a big step by announcing that they are lifting the mobility caveat on their forces. I hope that this will set an example for others."
Des Browne, Britain's defence minister, said: "That would be very welcome and opens up a potential for the south and east but we will have to wait until they announce what they're going to do."
Franz Josef Jung, Germany's defence minister, said his country wanted to triple its training efforts for Afghan security forces and hinted that Berlin could expand the limit on its force levels in Afghanistan beyond the current maximum of 3,500.
Jaap de Hoop Scheffer, Nato's secretary-general, said that trainers for the growing Afghan army were sorely needed, but he also urged Hamid Karzai, Afghanistan's president, to do more to tackle corruption.
"It is important that in Afghanistan that the other side of the medal which is the fight against corruption... is also taken very seriously," he said at the end of the two-day meeting.
"We are creating conditions for the development of a secure and stable environment, but that secure and stable environment needs the rule of law and needs the fight against corruption, it needs the fight against narcotics."
His call echoed those of world donors, who pledged $20bn at a meeting on Afghanistan in Paris on Thursday to rebuild the country but asked Karzai to increase the fight against corruption and to strengthen the rule of law.
The Nato-led International Security Assistance Force (Isaf) now comprises almost 53,000 troops from 40 nations, up from 33,000 troops 18 months ago, but commanders continue to press for more help.
In Bucharest, France agreed to send 700 additional troops, which will deploy later this year in an area near Kabul, Afghanistan's capital, in eastern Afghanistan.
This will free up around 1,000 US soldiers to move into the more violent south.
Around 3,500 US marines have also been deployed but they will leave by November.
Isaf has said it is trying to spread the influence of the weak central government across the country.
US General Dan McNeill, the former commander of Isaf, has said that 10,000 troops are needed for the effort.