The U.S. Senate Foreign Relations Committee has approved a resolution supporting Montenegro's membership in NATO, sending it to the full Senate for a vote.
The committee backed the small Balkan state's bid to join the military alliance last year, but it did not come up for a vote in the full Senate, where a two-thirds majority is required for approval of new NATO members.
Committee Chairman Bob Corker said on January 11 he hoped for "swift action" in the Senate this year.
Senator John McCain assured Montenegro's Prime Minister Dusko Markovic by phone that the U.S. Senate will ratify the accession agreement soon, the Montenegrin government press service said.
On January 10, Italy and Norway became the latest of 21 out of 28 alliance members that have already officially backed the agreement.
Montenegro's membership would represent the alliance's first expansion since Albania and Croatia joined in 2009. Although the country is a longtime ally of Russia, relations with Moscow have been uneasy recently, given its government's pursuit of closer integration with the West.
Montenegro also joined European Union sanctions against Russia over its annexation of Ukraine's Crimea in 2014.