WASHINGTON (Reuters) - The U.S. and Romanian governments are expected to announce on Friday completion of a new missile defense site south of Bucharest that will defend against potential attacks from Iran, according to three U.S. defense and government officials.

The U.S. embassy in Romania and Romania’s foreign affairs ministry will announce that the site, which includes a powerful radar, missile interceptors and communications equipment, is “technically capable,” said the sources, who were not authorized to speak publicly.

“That means all the major components of the missile defense system, including the missiles, are in place, and have been handed over to military commanders,” said one of the officials.

Military commanders will declare the so-called Aegis Ashore site operational, or ready for initial combat use, in early 2016 as they integrate the site with NATO’s broader ballistic missile defense system, the official said.

Navy Lieutenant Commander Tim Hawkins, a spokesman for the Navy, declined comment on the expected announcement, but said the site was “an important step in our efforts to protect against the growing threat posed by the proliferation of ballistic missiles of increasingly greater ranges, lethality and sophistication.”

Friday’s expected announcement comes after year of planning and work by the U.S. Missile Defense Agency, whose director, Vice Admiral James Syring, will be in Bucharest for the event.

It coincides with deliberations by U.S. officials about how to respond to an Iranian ballistic missile launch on Oct. 10 that violated U.N. Security Council resolutions.

The test has intensified concerns among U.S. lawmakers about an international nuclear deal in which Iran agreed to curb its nuclear program in exchange for relief from economic sanctions.

Riki Ellison, founder of the nonprofit Missile Defense Advocacy Alliance, said last week’s successful test of the Aegis Ashore off the coast of Hawaii paved the way for Friday’s event.

“This system is now in place to protect southern Europe from any specific threat from Iran should they decide to continue to break the treaty,” Ellison said.

In news first reported by Reuters, a team of sanctions monitors found on Tuesday that Iran violated a U.N. Security Council resolution by test-firing a missile capable of delivering a nuclear warhead.

A second U.S. official said the U.S. response to the Iranian test would likely be diplomatic, but noted that the U.S. Navy maintains a number of warships equipped with Aegis missile defense equipment in the Gulf region and in the eastern Mediterranean to guard against potential attacks from Iran.

Hawkins said there were currently four ballistic missile destroyers deployed to Rota, Spain, including two that were at sea, and four destroyers in the U.S. Central Command area, including two in the Gulf and two more heading there as part of the Harry S. Truman carrier strike group.

Syring told lawmakers in March that MDA was on schedule to complete the required military construction, installation, integration and testing at the Romania site to issue a “technical capability declaration” in 2015.