WASHINGTON — Former Republican Sen. Chuck Hagel Tuesday night called for the U.S. to facilitate a two-state resolution to the Israeli-Palestinian conflict, saying a peaceful end to the conflict is key to ensuring security for U.S. and Israel.

“The Israeli-Palestinian conflict is central, not peripheral, to U.S. vital security interests in combating terrorism,” said Hagel, who now is head of the Obama administration’s Defense Policy Board, which provides independent advice to Defense Secretary Robert Gates and other top officials on U.S. defense and security.

Hagel gave the keynote address at the first annual gala dinner of J Street, a progressive Jewish lobbying group that calls for the U.S. to pressure both Israelis and Palestinians to accept a two-state solution. The former GOP senator and one-time presidential hopeful addressed the role the U.S. should play in resolving the Arab-Israeli conflict and the consequences to the U.S. if it is not resolved.

“Only the Israelis and Arabs can decide [what to compromise],” he said. “But what we can do is facilitate a peace process,” although he did not specify exactly what steps the U.S. should take.

He advocated a two-state resolution as the most likely plan to gain support among Arab countries.

Hagel pressed the importance of strong relations with Arab countries. “U.S. has a long and special relation with Israel, but it must not come at the expense of our Arab relationships,” he said. “That is a false choice and not in the interest of Israel or the United States.”

Achieving peace also would help fight terrorism because terrorists use the Arab-Israeli conflict as a recruiting tool and they gain power the longer it lasts, he said.

Hagel, who represented Nebraska in the Senate, gained notoriety when he became one of the few Republican lawmakers to staunchly oppose the Iraq war during the Bush administration.

During Tuesday night’s speech, Hagel emphasized the relation of the Arab-Israeli conflict to the Iranian nuclear issue.

“Preventing an Iran nuclear weapon is a shared interest,” he said. “But sanctions have limited value,” adding that Iran uses the Middle East conflict as a reason for pursuing its nuclear ambitions.