U.S. 'committed' to Bulgaria's security

The United States remains committed to the security of its "important NATO partner" Bulgaria, U.S. Secretary of State Hillary Clinton says.

Clinton made the comments Sunday during an official visit to the Eastern European nation, in which she reiterated U.S. support for its security at a news conference in Sofia with Bulgarian Prime Minister Boyko Borisov.

"Let me say how committed the United States is to Bulgaria's security," Clinton said. "We are NATO allies. We take very seriously our Article 5 obligation for collective defense. Bulgaria has been an important, productive partner of NATO."

Thanking Bulgaria for its contribution of troops with the NATO-led forces battling Taliban extremists in Afghanistan, Clinton said the security cooperation between Washington and Sofia will only deepen over time.