(Adds U.S. officials say deployment of warships was never confirmed)
ANKARA, April 14 (Reuters) - The United States has cancelled the deployment of two warships to the Black Sea, Turkish diplomatic sources said on Wednesday, amid concerns over a Russian military build-up on Ukraine's borders.
Washington and NATO have been alarmed by the build-up near Ukraine and in Crimea, the peninsula that Moscow annexed from Ukraine in 2014. Last week, Turkey said Washington would send two warships to the Black Sea, in a decision Russia called an unfriendly provocation.
The U.S. Embassy in Ankara had notified Turkey's foreign ministry of the move, the sources said, but did not provide a reason. Turkey's state-run Anadolu news agency later reported that no new notices had been conveyed to Ankara for potential deployments at later dates.
U.S. officials said that Turkey may have misunderstood the initial notification and the deployment was never confirmed.
They said the United States frequently notifies Turkey for potential access to the Black Sea. But a request does not necessarily mean its ships will pass through, but rather ensures that if they choose to, they already have the required approval.
Russia, which warned Washington to stay far away from Crimea and its Black Sea coast, says the build-up is a three-week snap military drill to test combat readiness in response to what it calls threatening behaviour from NATO. It has said the exercise is due to wrap up within two weeks.
Ahead of the notification about U.S. warships, Russia's navy on Wednesday began a drill in the Black Sea that rehearsed firing at surface and air targets. NATO Secretary-General Jens Stoltenberg called on Moscow on Tuesday to end its troop build-up.
Turkish President Tayyip Erdogan has called for the "worrying" developments in eastern Ukraine's Donbass region to come to an end.
German Chancellor Angela Merkel and U.S. President Joe Biden on Wednesday called on Russia to pull back troops from Ukrainian borders.
Biden, in a phone call with Russian President Vladimir Putin on Tuesday, proposed a summit of the estranged leaders to tackle disputes and told Moscow to reduce tensions over Ukraine, the White House said. (Reporting by Tuvan Gumrukcu in Ankara and Idrees Ali in Washington; editing by Grant McCool)
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