The United States hopes to begin moving troops and equipment into Turkey as early as this week, preparing for an expected second front in a possible war with Iraq, Pentagon officials said Saturday.

They confirmed a tentative agreement on U.S. aid to Turkey, whose parliament could vote on the deal Tuesday. A Turkish official said the deal involved $5 billion in grants and $10 billion in loan guarantees from the United States.

But several U.S. officials said significant issues were still under negotiation. One American official said talks centered on the complex terms of the loan.

Turkey, a NATO ally and Iraq's northern neighbor, is pivotal for the Pentagon's plans for a two-pronged invasion of Iraq if President Bush decides on war. Talks dragged on for weeks on the U.S. request to base tens of thousands of troops in Turkey, whose citizens overwhelmingly oppose military action in Iraq.

At least a half-dozen U.S. military ships are waiting off Turkey's coast, part of a flotilla of more than three dozen vessels carrying equipment and supplies for the American ground troops.

In Crawford, Texas, where the president was spending the weekend on his ranch, White House spokesman Ari Fleischer said negotiations on final details of the deal with Turkey were continuing.

"And I anticipate they will continue for a little bit longer. I think it's fair to say that nothing is agreed to until everything is agreed to," Fleischer said.

U.S. war plans call for the Army's 4th Infantry Division, supported by elements of the 1st Infantry Division, to gather in Turkey for a possible thrust south toward Saddam Hussein's hometown of Tikrit and the capital of Baghdad.

The 4th Infantry's 17,000 troops are on alert for deployment but remain at their home bases -- Fort Hood, Tex., and Fort Carson, Colo. They would be flown to Turkey on passenger planes.

Pentagon officials and military analysts say attacking Saddam's military from two directions would mean a quicker battle with less risk for U.S. and allied military forces. Tens of thousands of U.S. troops already are massing in Kuwait, along Iraq's southern border.

Some details of the U.S.-Turkish pact still had to be worked out, officials from both countries said Saturday. Turkish Prime Minister Abdullah Gul said Saturday that the Cabinet would take up the issue of basing U.S. troops in the country, but did not give a date.

"The relationship between Turkey and the United States is important. We're discussing everything in the framework of mutual trust and respect," Gul told reporters. "Both sides have concerns. These concerns must be addressed in the best way possible."

For weeks, negotiators have been discussing a U.S. offer for aid that would help the Turkish economy if there were a war in neighboring Iraq. Turkey fears that a conflict could devastate its tourism industry, which brings in some $10 billion a year.

Turkey had been asking for $10 billion in grants and $20 billion in loans. The United States had been offering $6 billion in grants. A Western diplomat said each billion in grants could guarantee $10 billion in loans.

The agreement for $10 billion in loans and $5 billion in grants described by the Turkish official, therefore, would still cost the United States $6 billion.

Turkey's economy took a multibillion-dollar hit during the 1991 Persian Gulf War. Turkish leaders worry that a war now, with Turkey's economy in another slump, would mean even harder times.

Another issue is Turkey's request to send troops into northern Iraq in case of a war, a step that Turks say will guarantee stability on their border. Turkey already has tens of thousands of troops in northern Iraq to act as a buffer between the semiautonomous Kurdish groups there and Turkey's own restive Kurdish minority.

The United States also wants to make sure that Turkey does not try to seize lucrative oil fields near Mosul and Kirkuk in northern Iraq or take reprisals against Iraqi Kurds. Bush and other U.S. leaders have repeatedly said they want to ensure Iraq remains whole and stable after any conflict.