President Joe Biden said on Monday he held "positive and productive" talks with his Turkish counterpart, much of it just between the two of them to discuss how to proceed on a number of issues.

Speaking after attending a NATO summit in Brussels, Biden said his team and that of Turkish President Tayyip Erdogan would now work on nailing down the detail of what the two agreed on.

"I am confident we'll make real progress" in ties, Biden said.