BEIJING — A top Chinese general said Saturday that China’s newly created islands in the disputed South China Sea are intended mainly to aid shipping and dismissed concerns that Beijing is seeking to strengthen its control over the strategically vital region.

Gen. Fan Changlong’s remarks came as expectations grow that the U.S. might directly challenge Chinese claims in the South China Sea by sailing a Navy ship inside the 12-nautical mile territorial limit surrounding one of the man-made islands.

Concerns have been growing over the rapid appearance of islands created by piling sand atop reefs and atolls controlled by China, which is now adding, harbors, air strips and large buildings. The U.S. and others have called on Beijing to halt those projects, saying they are destabilizing an increasingly militarized region.

Fan said concerns that the island construction could affect freedom of navigation were unfounded.

“In fact, those construction projects are mainly carried out for civil purposes,” Fan told the Xiangshan Forum in Beijing. “As we have promised, the projects will not affect freedom of navigation in the South China Sea. Instead, they will enable us to provide better public services to aid navigation and production in the South China Sea.”

China’s assurances have failed to gain much traction abroad, and speaking shortly after Fan, Admiral Gary Roughead, the former U.S. Chief of Naval Operations, said the rapid expansion of the islands and a lack of clarity from Beijing “heightens suspicions and presents the potential for miscalculations.”

While Beijing’s assurances are welcomed, confidence measures and increased transparency are needed to assuage China’s neighbors of its peaceful intent, Roughead said.

Fan cited the recent launch of operations by two new lighthouses on Chinese island holdings as evidence of good intentions and said Beijing was committed to resolving disputes peacefully.

“We will never recklessly resort to the use of force, even on issues bearing upon sovereignty, and have done our utmost to avoid unexpected conflicts, said the general, a vice chairman of the powerful commission controlling the military that is headed by President Xi Jinping.

The ASEAN meeting and Xiangshan Forum are part of an effort by China’s military to burnish its reputation in a region wary of Beijing’s territorial ambitions. Four of the ASEAN countries have claims to seas and islands in the South China Sea that clash with Beijing’s own.

Unnamed Pentagon officials said last week that the U.S. Navy may soon receive approval to sail a ship inside the 12-nautical mile territorial limit surrounding China’s man-made islands, reported the Navy Times, which is closely affiliated with the U.S. Navy.

ASEAN member Philippines on Wednesday gave strong backing for such a move.

Sailing within the boundary would mark the first time the U.S. has directly challenged China’s territorial claims since 2012 and reinforce Washington’s assertion that land reclamation does not add sovereign territory.

China’s military, especially its navy, is gathering formidable capabilities, fueled by large annual increases in the military budget, which is now the world’s largest behind the U.S.