NEW YORK (AP) _ The sister of hostage Terry Anderson says it's ''unthinkable'' that the United States could win widespread Arab support for the Gulf War but fail to gain freedom for Americans imprisoned in Lebanon.

Peggy Say urged President Bush to keep U.S. troops in the Persian Gulf region until American prisoners of war and the hostages are freed.

''My plea now to the administration is: 'Do not leave the Persian Gulf until you wrap your arms around every single POW and bring them home.' And while you're at it, you just grab my brother and the rest of them, too, and let's get this over with,'' she said Thursday while taping the ''Donahue'' show.

''It would just simply be unthinkable to have gone through all of this in the Middle East and be unable to get six hostages out,'' Mrs. Say said after taping the show. ''They're going to do it this time. I'm sure of it.

''If there is reconciliation, if the hostages' release plays even a tiny part in reconciliation with Iran, reconciliation with Syria, an end to the chaos in Lebanon, I will not begrudge one single day of Terry's captivity - and neither would he. Let it mean something,'' she said.

The U.S.-led coalition against Iraq includes Syria, the major power broker in Lebanon. Iran is neutral in the war.

Say appeared on Phil Donahue's talk show with Alice Bonar and Junius Hunter, the sister and brother of U.S. Marine Chief Warrant Officer Guy Hunter, a prisoner of war; Leo Rathbun, the father of Army Spc. Melissa Rathbun-Nealy, listed as missing in action; and Carmella La Spada, founder of No Greater Love, a group that aids such families.

Anderson, 43, the chief Middle East correspondent for The Associated Press, was kidnapped in Beirut on March 16, 1985. He is the longest held of six American hostages.

''I've been told the captors want it over with. Their demands have been met. Walk away,'' said Mrs. Say, who has frequent contact with the State Department.

Iraq's invasion of Kuwait Aug. 2 reportedly led to the release or escape of a group of Shiite prisoners in Kuwait whose freedom had been a key demand of Anderson's captors.

''Their Kuwaiti jailers freed them,'' Mrs. Say said. ''We've had that confirmed by the State Department. Right or wrong, those men are free and my brother is not.''

She said some of the prisoners returned to Lebanon and the rest fought in the Kuwaiti underground ''because they were enemies of the Iraqi regime.''

The prisoners were jailed in Kuwait for terrorist activities and are thought to be relatives of members of the group holding Anderson.

Mrs. Say called President Hashemi Rafsanjani of Iran the key to the hostages' release. Iran has clout with Shiite Moslems holding Anderson and the others.