FILE PHOTO: A U.S. soldier from Dragon Troop of the 3rd Cavalry Regiment fires a Javelin missile system during their first training exercise of the new year near operating base Gamberi in the Laghman province of Afghanistan January 1, 2015. REUTERS/Lucas Jackson

KIEV (Reuters) - Ukraine has received the first U.S. Javelin missiles and launch units, Ukrainian President Petro Poroshenko said on Monday.

In March the U.S. State Department approved the possible sale of Javelin systems to Ukraine at an estimated cost of $47 million.

“I can confirm that the long-awaited weapon arrived in the Ukrainian army” Poroshenko said on Facebook.

Kiev and Washington believe that the Javelin system will help Ukraine build its long-term defense capacity.

The United States has been one of Kiev’s staunchest supporters since Moscow’s annexation of Crimea in 2014 and the subsequent outbreak of fighting in Ukraine’s eastern Donbass region that has killed more than 10,000 people.

But the decision to provide lethal aid was sensitive and Russia has repeatedly said supplying weapons to Ukraine would further destabilize the situation by encouraging Kiev to use force.