As U.S. hopes dwindled of going through Turkey for an attack on Iraq, the Bush administration took back its offer to give $15 billion in aid to Turkey in exchange for military cooperation, officials said Saturday.

U.S. commanders have been eager to use the NATO ally to open a northern front in any invasion of Iraq. Staging in Turkey would allow more U.S. troops and heavier equipment to push toward Iraqi leader Saddam Hussein's hometown of Tikrit.

The two countries had negotiated a package of U.S. grants and loans aimed at boosting Turkey's ailing economy, which is expected to suffer even more if there is war.

Earlier this month, Turkey's parliament -- mindful of polls showing a vast majority of the public opposed war -- rejected a government motion to authorize the deployment of 62,000 American troops on Turkish soil.

Turkey has since delayed a final decision, and the new prime minister, Recep Tayyip Erdogan, said Saturday a second vote was at least another week off.

Now, the $15 billion is off the table, said two senior U.S. officials, speaking on condition of anonymity.

Nonetheless, Pentagon officials said Saturday there are no immediate plans to move any more U.S. military forces or equipment away from Turkey.

Meanwhile, the White House's special envoy to the Iraqi opposition was in Ankara holding talks at the Turkish Foreign Ministry. Zalmay Khalilzad's primary mission during the Friday meeting was to persuade Turkey not to send its troops into northern Iraq, as the United States had agreed to allow as part of the negotiated aid package, one of the officials said.

Khalilzad warned that such intervention would be a "tragedy" for U.S.-Turkish relations, another official said.

Turkey already has thousands of troops in Kurdish areas of northern Iraq and has said it plans to send more in the event of a U.S.-led invasion. Turkey worries that the political aspirations of its own sizable Kurdish minority would be boosted if Iraqi Kurds win more independence.

But the United States, which insists it wants Iraq's current territorial boundaries to remain intact, hopes to keep violence from flaring in the volatile region now controlled by two autonomous Kurdish factions.

U.S. military commanders and White House officials repeatedly have said they have other plans that, although costlier and riskier, allow for operating in northern Iraq without sending troops in from Turkey.

But Pentagon officials said about three dozen ships with equipment for the Army's 4th Infantry Division will remain for now off Turkey's coast, where they have been for weeks. Other troops and equipment are still surging into Kuwait and the 4th Infantry's troops are still at their home base of Fort Hood, Texas, the officials said.

It was not decided whether the U.S. aircraft carriers Theodore Roosevelt and Harry S. Truman would stay in the eastern Mediterranean or follow the other ships in their battle groups, armed with Tomahawk cruise missiles, that already relocated to the Red Sea.

Staying in the Mediterranean mean the carriers' planes might have to fly over Turkey to strike targets in northern Iraq. Turkey has not granted the United States the rights to fly warplanes or cruise missiles over Turkey to attack Iraq.

The U.S. aid package was withdrawn because it was linked to a certain time frame, said one official. It was not clear if the package could be renegotiated if Turkey were to later approve a U.S. troop deployment.

Meanwhile, U.S. forces continued upgrading some Turkish military bases, under a previous agreement that was meant to pave the way for American use of those bases. Workers continued unloading gear for that purpose at Turkish ports Saturday, but not the tanks, helicopters and other U.S. weaponry waiting in ships offshore.