A French-led amphibious force postponed joint beach attack drills in the Western Pacific on Friday after a landing craft ran aground, commanders said.
The military exercise in Guam is a first. It involves US troops, British and Japanese helicopters and landing craft launched from France's amphibious carrier Mistral.
It had been meant as a show of force to counter China's growing military power in the region.
But Friday's mishap could blunt its intended message.
The exercise was halted after a French landing craft ran aground, damaging one of its propellers. A separate helicopter landing drill was also cancelled, a spokesman for Japan's Self Defence Forces said later.
China is extending its influence beyond its coastal waters and the South China Sea into the Pacific by acquiring aircraft carriers. France controls several islands in the Pacific, including New Caledonia and French Polynesia.
France is seeking stronger economic ties with Beijing but, along with Britain, is also looking to balance China's expanding power by deepening security cooperation with Japan, Asia's second-strongest naval power after China, and the United States.
The Mistral is leading the Jeanne d'Arc amphibious task force in a tour through Asia. The French defence ministry, in summary of the mission, described it as "a potent support to French diplomacy."
The Mistral, which left France in February, can carry up to 35 helicopters and four landing barges, as well as several hundred soldiers. The ship visited Japan this month before heading to Guam.
The exercise "further builds our partnerships in the region to provide a reasonable assurance to those who may not agree with us too much that we are ready at all times," Captain Jeff Grimes, the US Navy's chief of staff in the region, said on the beach where the practice landings were meant to have taken place.