WASHINGTON -US President Barack Obama defended his endorsement of Israel's 1967 boundaries as the basis for a future Palestine, telling America's pro-Israel lobby that his views reflected long-standing US policy that needed to be stated clearly.

He also said on Sunday that the Jewish state will face growing isolation without "a credible peace process".

Obama tried to alleviate concerns that his administration was veering in a pro-Palestinian direction, placing his Middle East policy speech on Thursday in the context of Israel's security. He told the American Israel Public Affairs Committee that those border lines must be subject to negotiated land swaps and said these principles reflected US thinking dating to president Bill Clinton's mediation efforts.

"If there's a controversy, then it's not based in substance," Obama said in a well-received speech at a Washington convention center. "What I did on Thursday was to say publicly what has long been acknowledged privately. I have done so because we cannot afford to wait another decade, or another two decades, or another three decades, to achieve peace."

The event was eagerly anticipated after Obama outlined his vision for the changing Middle East at the State Department on Thursday and then clashed in a White House meeting with Israeli Prime Minister Benjamin Netanyahu a day later.

The speech came ahead of a week-long trip for the president to Europe, where he will tend to old friends in the Western alliance and look to secure their help with the political upheaval across the Arab world and the decade-long conflict in Afghanistan.

Netanyahu said in a statement after Obama's remarks that he supported the president's desire to advance peace and resolved to work with him to find ways to renew the negotiations. "Peace is a vital need for us all," he said.

The Israeli leader's tone was far more reserved than last week, when he issued an impassioned rejection of the 1967 borders as "indefensible" and even appeared to publicly admonish Obama after their White House meeting.

Netanyahu was scheduled to address the pro-Israel lobby on Monday night and Congress on Tuesday. Obama didn't retreat from his remarks on what it would take to reach a two-state solution between Israelis and Palestinians.

Associated Press