President Barack Obama’s national security adviser, Susan Rice, all but ruled out the U.S. joining Turkey to create a militarily protected safe haven in Syria to shelter civilians and opposition fighters.

Turkey, a key ally in the coalition against Islamic State, has been pressing the Obama administration to deepen its involvement in the Syrian civil war by establishing a no-fly zone along the Turkey-Syria border to protect civilians and weaken the control of Syrian President Bashar al-Assad.

“We are not moving in the direction of a no-fly zone or a safe haven at this point,” Rice said.

While talks continue, she said that for now the administration doesn’t consider such action to be in the U.S. interest, which is first to defeat Islamic State extremists in Iraq.

“We think the establishment of a no-fly zone or a safe zone, at this point, is at best premature, and would be a major investment of resources that would be something, frankly, of a diversion from the primary task at hand,” Rice said today at a forum held by the Wall Street Journal.

Rice dismissed reports this week that the U.S. and Turkey are narrowing their differences in talks in which Turkish officials have linked an agreement on a no-fly zone to permission to use the Incirlik airbase in southern Turkey.

Using that major airbase would cut the flight time from the Persian Gulf region for U.S. jets attacking targets in Iraq and Syria.

‘Gotten Ahead’

Those reports have “gotten ahead of the policy discussions,” Rice said.

Rear Admiral John Kirby, the U.S. Defense Department’s top spokesman, today said creating a buffer zone is “an interest of high concern for the Turkish government.”

“But at this time, we don’t believe that that’s going to be a useful solution to the situation inside Syria,” he said.

For the U.S. military, Kirby said, creating a no-fly zone would require additional resources and involve “additional operational risk. And you have to weigh that against the overall benefits of doing it.”

“These are complicated missions that require a lot of time, effort, resources, and you have to incur certain risk, and you’ve got to fully understand what those risks are before you,  you know, you launch off on something like that,” he said.

Another U.S. official involved in the talks said today that while the U.S. and Turkey have resolved some of their differences, a number of significant ones remain. The official requested anonymity to discuss diplomatic negotiations.

‘Increasingly Important’

Turkey is supporting the anti-Islamic State effort by curtailing transit by foreign fighters and oil smuggling by the Islamic extremist group, as well as hosting a prospective training program for vetted Syrian moderates to begin next year.

Turkey “could play an increasingly important role on the military side, if it chose to do so,” Rice said.

While U.S. defense officials said Turkey’s agreement to allow limited training of Syrian rebels on its soil is a positive step, they cautioned that it’s not likely to make a significant change in the battle against Islamic extremists.

First, said one of the officials, who like the others requested anonymity to discuss the issue, it will take months and perhaps as much as a year to recruit, vet, train and equip even 2,000 volunteers. Already, the official said, the U.S. is having difficulty identifying moderate recruits who are unlikely to defect to extremist groups.

So far, Turkish officials have refused to allow the use of the airbase at Incirlik for airstrikes against extremist targets, in part because they want the air campaign expanded to Syrian airbases and other military targets, according to one of the U.S. officials.

Turkish Lobbying

Despite lobbying from Turkey and Saudi Arabia, as well as Republican U.S. lawmakers, the Obama administration so far has resisted expanding the air war, which would require destroying or suppressing Syria’s air defenses.

On Capitol Hill, there was bipartisan criticism of Turkey today for what some lawmakers said they consider halfhearted support for the anti-Islamic State fight.

Representative Paul Cook, a California Republican, called Turkey a “squishy ally” during a hearing on foreign fighters held by two subcommittees of the House Foreign Affairs Committee.

“A number of us on this committee and the House Armed Services Committee are very, very nervous about Turkey and its reluctance to have strike aircraft be flown from Incirlik,” he said.

Representative David Cicilline, a Democrat from Rhode Island, said there are “real questions” about Turkey’s actions.

“It’s pretty clear that they have not been an enthusiastic, wonderful, reliable partner in this effort,” he said.