Washington ? President Barack Obama on Friday rejected his transportation secretary’s suggestion that the administration consider taxing motorists based on how many miles they drive instead of how much gasoline they buy.

“It is not and will not be the policy of the Obama administration,” White House press secretary Robert Gibbs told reporters, when asked for the president’s thoughts about Transportation Secretary Ray LaHood’s suggestion, raised in an interview with The Associated Press a daiy earlier.

Gasoline taxes that for nearly half a century have paid for the federal share of highway and bridge construction can no longer be counted on to raise enough money to keep the nation’s transportation system moving, LaHood told the AP.

“We should look at the vehicular miles program where people are actually clocked on the number of miles that they traveled,” the former Illinois Republican lawmaker said in the AP interview.

LaHood spokeswoman Lori Irving said Friday that the secretary was speaking of the idea only in general terms, not as something being implemented as administration policy.

Most transportation experts see a vehicle miles traveled tax as a long-term solution, but Congress is being urged to move in that direction now by funding pilot projects.

The idea also is gaining ground in several states. The governor of Idaho is talking about such a program. A North Carolina panel suggested in December the state start charging motorists a quarter-cent for every mile as a substitute for the gas tax. Rhode Island’s governor, however, has expressed opposition to a panel’s recommendation in December that the state charge motorists a half-cent for every mile driven in addition to the gas tax.

A tentative plan in Massachusetts to use GPS chips in vehicles to charge motorists by the mile has drawn complaints from drivers who say it’s an Orwellian intrusion by government into the lives of citizens. Other motorists say it eliminates an incentive to drive more fuel-efficient cars since gas guzzlers will be taxed at the same rate as fuel sippers.

Besides a VMT tax, more tolls for highways and bridges and more government partnerships with business to finance transportation projects are other funding options, LaHood, one of two Republicans in Obama’s Cabinet, said in the interview Thursday.

“What I see this administration doing is this — thinking outside the box on how we fund our infrastructure in America,” he said.