ABOARD A U.S. MILITARY AIRCRAFT — Defense Secretary Ash Carter said Monday that he will speak with NATO allies in Brussels this week about increasing their financial contributions to 2 percent of gross domestic product that each member promised.

“You can bet that a continuing theme here and in Warsaw will be the need for all countries to meet their pledged 2 percent and, of course, ideally more,” Carter told reporters aboard his plane just before landing in Brussels. “Absolutely for sure I will be emphasizing that.”