BRUSSELS (AP) — U.S. Secretary of State John Kerry brought senior Afghan and Pakistani officials together Wednesday for security talks aimed at improving relations between the two nations ahead of next year's withdrawal of NATO combat forces from Afghanistan.

Kerry met Afghan President Hamid Karzai and Pakistani military chief Gen. Ashfaq Parvez Kayani at Truman Hall, the secluded estate on the outskirts of Brussels that is home to the U.S. ambassador to NATO. Kerry said as he opened the meeting that the talks were important, as Afghanistan is currently in a "critical transformational period."

The meeting lasted about three hours and included lunch and a stroll around the estate's manicured gardens, but apparently did little to ease the tension between Afghanistan and Pakistan as all sides try to lure the Taliban to peace negotiations.

"It's fair to say that there is a good feeling among all of us that we made progress in this dialogue. But we have all agreed that results are what will tell the story, not statements at a press conference," Kerry told reporters after the meeting.

"We have a lot of homework to do. We are not going to raise expectations or make promises that can't be delivered," he said, noting it was better to "under-promise but deliver."

Ties between Afghanistan and Pakistan have long been strained over links between Pakistan's security apparatus and the Taliban. The U.S. supports Afghan-Taliban reconciliation but Karzai has said the effort must have Pakistan's backing to succeed.