WASHINGTON (AP) _ Israeli Prime Minister Benjamin Netanyahu said today he and Palestinian leader Yasser Arafat had achieved a breakthrough on a long-elusive deal to turn over more West Bank territory, and President Clinton asked them to return next month to iron out a final deal.

``I believe that we all agreed that we have made progress on the path to peace,'' Clinton told reporters after an hourlong session with the two leaders in the Oval Office. He described ``a significant narrowing of the gaps between the two parties across a wide range of issues.''

But Secretary of State Madeleine Albright steered clear of claiming a breakthrough on any of the tough issues, including how much land Israel would relinquish and what the Palestinians would do to curb terrorism.

``This process needs to be speeded up,'' Albright said.

She and U.S. mediator Dennis Ross will go to the Middle East for more talks with the two leaders around Oct. 6, and about a week later Arafat and Netanyahu will return to the White House to see Clinton again.

The two Middle East leaders flew to Washington today following talks that lasted late into Sunday night with Albright in New York. After their three-way session in the Oval Office, Netanyahu and Clinton were holding a one-on-one meeting, and Clinton is to meet Arafat separately on Tuesday.

``I think we're getting close to finalizing an agreement and it's time for the leaders to meet,'' Netanyahu said on NBC's ``Today'' show before the White House meeting.

In his remarks to reporters, Clinton did not mention details. Earlier, Israeli diplomats, speaking on condition of anonymity, said there was agreement that Israel would withdraw from an additional 13 percent of the West Bank _ adding to the 27 percent already promised to the Palestinians.

Three percent would be turned into a nature preserve and kept under Israeli military control, with Israeli and Palestinian construction prohibited.

Clinton cautioned that some obstacles remained.

``There is still a substantial amount of work to be done until a comprehensive agreement can be reached,'' he said.

In the Oval Office, Clinton stood between Netanyahu and Arafat in front of an unlit fireplace. They faced a wall of cameras and correspondents yelling questions over each other. Clinton hushed the reporters once for a question.

Both Netanyahu and Arafat looked straight ahead, stone-faced, as Clinton spoke. Arafat's eyes roamed tentatively as he took in what his interpreter was saying. Netanyahu only briefly looked at Clinton as the president noted the ``very unusual commitment'' both Mideast leaders were making to negotiating peace.

Albright watched from the edge of the crowd. She paused as Netanyahu, then Clinton, left the room. Arafat stopped, guided her ahead of him and walked with her, his hand in the small of her back. He turned back and gave a small nod to reporters before he disappeared through the door.

In his remarks to NBC today, Netanyahu spoke of the West Bank withdrawal.

``That's basically the concept we're trying to nail down here, and that's where we've made a breakthrough,'' Netanyahu said. He said he expected additional talks, ``possibly in the near future, and yes, I would perk up your ears.''

Israel's acceptance of a U.S. demand that it relinquish another 13 percent of the land it captured in the 1967 Six-Day War cleared a major hurdle to a West Bank agreement with the Palestinians.

The White House talks could determine the course of the Arab-Israeli conflict and, if successful, add to the politically troubled president's luster as a peacemaker.

Persuasive in steering Protestants and Catholics to an accord in Northern Ireland, Clinton hopes to use it as an example for Arabs and Israel in the Middle East and other adversaries around the world.

Albright called her meeting with Netanyahu and Arafat important, but declined to discuss the substance of what was discussed, saying only, ``We still have a lot of work to do.''

Diplomatic sources said a promise by Arafat to tone down the speech he is due to make to the U.N. General Assembly in the afternoon had improved the atmosphere for peacemaking.

Arafat, though, declined to respond to reporters' questions about what specific measures he may be willing to take to assure the Israelis they would be safe in giving up more land.

Israel's ambassador to the United Nations, Dore Gold, said in an interview Sunday that ``if there's no security, there is no deal.''

With the accord hanging in the balance, Albright shuttled between Netanyahu and Arafat for a second day before bringing them together under U.S. supervision for the first time in nearly a year.

``It was an important meeting,'' Albright told reporters. ``It was very important to have it. I am not going to talk about the substance of it. But I am very glad we had the meeting.''

State Department spokesman James Rubin said ``it means they are intensifying their efforts,'' and that he would not dispute Israeli assertions that the territorial issue was basically resolved.

There ``is a lot more work to be done on security because of the nature of it, and it is more complex,'' Rubin said.

And a senior administration official added that not all the details of a West Bank agreement were likely to be settled over the next few days.

Netanyahu, in a speech at Hunter College, stressed a need for Israeli civilians to be protected from attack from the West Bank or Gaza.

He said the remaining issue was ``to make sure that the land that we hand over to the Palestinians does not become a base for continued terrorist attacks against Israel.''

Gold said Arafat's Palestinian Authority must break up terrorist cells on land it already holds on the West Bank and in Gaza and confiscate weapons.