General Pierre de Villiers said the four fighter aircraft, either Mirage 2000 or Rafale jets, would fly from a base in Poland, amid growing anxiety in Baltic countries over Russia's intervention in Ukraine.

"They will participate in the air policing mission over the Baltic states, from Poland," he told reporters.

In another measure of "reassurance," France also is deploying an AWACS early-warning radar aircraft to patrol the skies over Romania, the general said.

The United States announced Tuesday it was deploying 600 airborne troops for exercises in Poland, Latvia, Lithuania and Estonia in a show of solidarity with NATO members bordering Russia.

But the French officer said his political leaders had not ordered further steps to support alliance members.

"For the moment, the guidance is very clear, we do not go beyond that," he said.

The French military, which is overseeing the land element of NATO's response force through 2014, would be ready to expand its presence in Eastern Europe as required, he added.

The Baltic states, which gained independence from the former Soviet Union in 1991, joined NATO in 2004 but lack sufficient aircraft to police their own skies, so larger NATO members take turns patrolling their airspace.

During his visit to Washington, de Villiers met White House officials and the chairman of the US Joint Chiefs of Staff, General Martin Dempsey, for talks that touched on military cooperation in Africa's Sahel region.