NATO leaders are challenging Russian claims about a withdrawal of troops from areas around Ukraine. Defense ministers from the alliance met in Brussels on Wednesday to address the buildup of Russian troops along the border.

Secretary General Jens Stoltenberg said Russia maintains what he called a "massive invasion force." He said the alliance could prove that with satellite imagery. He did not provide any evidence.

Stoltenberg called on the Russians to engage in diplomatic efforts in good faith. At the same time, the ministers directed commanders to draw up plans for new combat units in Romania and other member nations nearby.

Russian defense ministry officials have said some of their troops have completed their exercises and are returning to their bases. They released video of tanks and other vehicles being loaded onto trains.

Stoltenberg said the Russians have contested the principles that have underpinned NATO security for decades. He said that's the "new normal" and suggested member nations need to be "prepared for the worst."