U.S. mindful of Gulf concerns during Iran nuclear talks: official

The United States will remain " very mindful" of concerns of the Gulf states as it seeks to strike a comprehensive nuclear deal with Iran, a senior American diplomat said Wednesday.

"We will not relent in our efforts to confront Iran's destabilizing behavior ... and not relent in enforcing existing sanctions," said Deputy Secretary of State William Burns at an event in the Center for Strategic and International Studies.

U.S. concerns with Iran extend far beyond the nuclear issue, across a range of dangerous Iranian behavior that threatens interests of the U.S. as well as countries in the region, said Burns, who also pledged continued American efforts to intensify consultations and cooperation with the Gulf states over a range of issues, citing Secretary State John Kerry's visit to the United Arab Emirates Tuesday and President Barack Obama's upcoming trip to Saudi Arabia next month.

Burns emphasized that Iran's nuclear issue remains the "most urgent", vowing that the U.S. will pursue diplomacy with "eyes wide open." "We have no illusions about Iran's intentions or its conduct."

Iran and the P5+1, including the United States, Russia, China, France, Britain and Germany, on Tuesday started the new round of talks in Vienna, the Austrian capital, with the hope of striking a comprehensive agreement on Tehran's controversial nuclear program.

The P5+1 and Iran reached the first step interim agreement in November, which came into effect on Jan. 20. Under the interim agreement, Iran suspended the most sensitive parts of its nuclear activities in exchange for partial relief of the sanctions slapped on it.

U.S. State Department spokeswoman Marie Harf told reporters Wednesday that the current talks in Vienna had been "constructive and useful."