— French President Nicolas Sarkozy lashed out Friday at the U.S. commitment to the NATO effort in Libya, saying that Europe was bearing the main burden of the effort, despite American complaints to the contrary.

The remarks came on the same day that the House of Representatives took up a largely symbolic bill to limit U.S. funding for the mission, and at the end of a week of political splintering over the future of the NATO action, which has stretched far longer than many politicians expected.

Sarkozy said that France and Britain were the main contributors to the effort to bring an end to Moammar Gaddafi’s rule, and he vowed to keep up the pressure so long as Gaddafi remains. He also condemned the notion that the future of NATO was in doubt because of European reluctance to devote resources to their militaries, something retiring Secretary of Defense Robert M. Gates suggested in a speech this month.

“I’m not of the opinion that the bulk of the work in Libya is being done by our American friends,” Sarkozy said in remarks to reporters at a European Union summit in Brussels. “We must continue until Mr. Gaddafi leaves.”

As for Gates, Sarkozy said, his comments about European military might — or lack thereof — were “unfair,” stemming from “a bit of bitterness.”

Questions over the future of the Libyan mission reached new heights this week, as the bombing campaign stretches into its fourth month with no immediate end in sight for Gaddafi. An errant missile strike this week that apparently hit a residence in Tripoli, killing civilians, has further put political pressure on the mission. Italy’s foreign minister, Franco Frattini, called Wednesday for an immediate halt to hostilities to allow for humanitarian aid to reach the country.

The White House has said that American forces have flown about a quarter of the more than 12,000 sorties over Libyan soil, and American officials have also acknowledged that both U.S. drones and jets continue to occasionally drop bombs on Libya.