The White House on Thursday downplayed the risk of war between Iran and the United States, despite Iranian missile tests and some tough talk by US Secretary of State Condoleezza Rice.

Asked about an apparent contradiction between Rice's comment about tightening US security in the Gulf and those made earlier by Defense Secretary Robert Gates on Wednesday, Tony Fratto, a White House spokesman, said "I think secretary Gates was very accurate" about risks not having increased.

Gates told reporters he did not believe there was increased risk following a string of missile tests, including one of a missile capable of hitting Israel.

"Secretary Gates was right, there is no particular increase," Fratto said.

And Iran on Thursday moved ahead with new missile tests in the Gulf.

Rice warned Iran that Washington had beefed up its security presence in the Gulf and would not hesitate to defend Israel and other allies.

"We will defend American interests and the interests of our allies," Rice said, answering a question on an Iranian threat to "set fire" to Israel.

"We take very strongly our obligation to defend our allies and we intend to do that," she said at a news conference on a visit to Tbilisi, Georgia.

"In the Gulf area, the United States has enhanced its security capacity, its security presence and we are working closely with all our allies... to make (sure) they are capable of defending themselves," she said.

Fratto did not give details on any security measures the United States may have taken in the region.