United States President Donald Trump is heading to Ankara where NATO will hold its two-day annual summit starting Tuesday. File Photo by Yuri Gripas/UPI | License Photo

July 7 (UPI) -- Leaders of the Western world's premier military alliance will gather in Ankara on Tuesday for the start of this year's NATO summit, with support for Ukraine and questions over U.S. President Donald Trump's commitment to the pact expected to dominate the two-day meeting.

The summit in Turkey's capital is formally focused on reviewing progress made since last year, when the leaders of NATO's 32 members agreed to raise their annual defense-related spending from the previous 2% target to 5% of gross domestic product by 2035 amid growing global security concerns.

Major new policy pronouncements are not expected, though several large arms deals are. The focus of the two-day summit will be on progress toward that defense-investment plan and how allies intend to spend the money to increase weapons production, cooperation and joint procurement.

Attention will also be on Trump and the U.S. commitment to NATO after his administration announced earlier this year that it would withdraw some American troops from Germany.