Libyan rebel fighters help themselves to weapons from an abandoned Gaddafi ammunition dump bombed by NATO a few days ago, approximately 25 miles southeast of Zintan. (Anis Mili/Reuters)

French officials announced Wednesday that they had armed rebels in Libya, marking the first time a NATO country has said it was providing direct military aid to opponents of the government in a conflict that has lasted longer than many policymakers expected.

France dropped light armaments, including guns and rocket-propelled grenades, in the Nafusa Mountains in western Libya in early June to help rebel forces who were “in a very deteriorating situation” under threat from the Libyan military, a French military spokeswoman said.

The decisionsmarks a new step in the international military intervention in Libya, which has entered its fourth month. NATO has been careful to limit its contact with the rebels, citing ground rules that restrict it to protecting civilians, not explicitly choosing sides in the battle between anti-government forces and Libyan leader Moammar Gaddafi’s military.

The rebels — who are often poorly trained and equipped — have complained that the international alliance is ignoring them.

Britain said Thursday it is providing body armor, police uniforms and communications equipment to help Libya’s opposition protect rebel leaders and international officials based in the country’s eastern cities, the Associated Press reported.

British Foreign Secretary William Hague said in a statement that London was offering 5,000 sets of body armor, 6,650 uniforms, 5,000 high-visibility vests and communications equipment for police loyal to Libya’s opposition.

The French announcement seemed sure to provoke critics who have already said that NATO is overstepping the boundaries of the U.N. Security Council resolutions that authorized the intervention. The Dutch defense minister, Hans Hillen, warned against “mission creep” while speaking to reporters in Brussels on Wednesday and called for a political solution to the crisis, news services reported.

The French military spokeswoman, Lt. Stephanie Lugrin, said the decision to drop weapons along with humanitarian aid was made because the French government thought that villagers in the Nafusa Mountains were in imminent peril from Libyan forces.

Libya’s government condemned the weapons drop. “NATO and France are clearly not interested in the safety of civilians,” said spokesman Moussa Ibrahim. “What right does NATO have to support the rebels?”

Le Figaro, the daily Paris newspaper, was the first to report the French aid, citing government sources who said France had judged that the rebels in the mountains had the best hope for mounting an assault on the capital.

The newspaper reported that the decision was made without consulting France’s NATO allies, and a NATO spokeswoman declined to comment on the reports Wednesday.

NATO has imposed a no-fly zone over Libya, and specially equipped alliance jets circling the Mediterranean keep watch over the nation’s airspace, suggesting that NATO allowed the French planes to fly over Libyan territory on a non-NATO mission.

As the conflict has continued, some policymakers and military personnel in NATO countries, including the United States, Britain and Italy, are questioning how long the Western commitment can last.

Arming rebels could ease the way for an advance on Tripoli, and in the past week anti-government forces have made gains in the mountain area where the weapons were dropped.

But countries have disagreed about whether the U.N. security resolution that imposes an arms embargo against Libya extends to the rebels as well.

Lt. Gen. Charles Bouchard, the Canadian commander of the NATO effort, told The Washington Post last weekend that he thinks that Gaddafi’s power is weakening and that the momentum is against Libya’s longtime leader.  

Staff writer Ernesto Londono in Tripoli contributed to this report. Birnbaum reported from Berlin.