BAGHDAD -- Defense Secretary Robert M. Gates urged the Turkish military yesterday to abandon its invasion of guerrilla-controlled lands in the northernmost reaches of Iraq by mid-March, amid signs that the American and Iraqi governments are increasingly worried that fierce fighting along the mountainous Turkey-Iraq border could widen into a broader and bloodier conflict.

"It's very important that the Turks make this operation as short as possible and then leave," Gates told reporters in India yesterday as he prepared to leave for Ankara, Turkey's capital. His comments seemed to depart from earlier U.S. statements backing the Turks in their operations against guerrillas from the Kurdistan Workers' Party.

"I measure quick in terms of days, a week or two, something like that, not months," Gates said, becoming the first senior American official to demand a strict timeline for the Turkish operation to end.

As U.S. officials worried that the worsening fighting could destabilize Kurdish-controlled northern Iraq, political momentum hit a roadblock in Baghdad yesterday: The three-member Iraqi presidency council rejected an important new law passed this month that calls for provincial elections by October.

The law would presumably do away with severe electoral distortions in some provinces that exist partly because Sunnis boycotted the previous provincial ballots, leaving Kurds and Shiites with vastly more power. For example, Shiites dominate the Diyala provincial government, though Sunnis account for a majority in the region, a situation that exacerbated the sectarian violence there during the past two years.