"I have noted a broad support from all ministers on this counter-insurgency approach, but without discussing the resource implications of these recommendations," he added.
The BBC's Nick Childs, in Bratislava, says that although the stakes are high for all countries involved in the Nato-led force in Afghanistan, everything still hinges on what President Barack Obama decides in his review of Afghan strategy.
Mr Gates again declined to endorse Gen McChrystal's approach, saying he was in Bratislava to listen and consult.
"Clearly one of the things that I think the president is expecting from me is to bring back the views of our allies on some of these issues," he said.
Mr Gates told reporters that he did not seek specific promises of military assistance, and none was given.
"There were a number of allies who indicated they were thinking about, or were moving toward, increasing either their military or their civilian contributions, or both, and I found that very heartening," said Mr Gates.
Our correspondent says other member states are waiting for the outcome of the Afghan presidential election run-off before deciding on a course of action.
Earlier, the top UN envoy in Afghanistan, Kai Eide, supported calls for more troops to be sent to the country.
Mr Eide said more countries needed to commit soldiers to the Nato operation.
"Let me say this is not a military process, it can't be done solely by the military," he said. "It has to be a political process, done by the politicians and the Afghan leadership."
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