A US Navy minesweeper that has been stuck on a World Heritage-listed coral reef in the Philippines since last week ignored warnings to avoid the area, a government official said on Monday.
The comments from the superintendent of Tubbataha marine park, Angelique Songco, added to growing anger in the Philippines over the incident, for which the US Navy has apologised but may still face fines.
Park rangers radioed the USS Guardian to advise it was nearing the Tubbataha Reef on Thursday, but the ship captain insisted they raise their complaint with the US embassy, Songco told reporters.
She said shortly after the warning, the 68-metre (224-foot) vessel became stuck on part of Tubbataha Reef, a UNESCO World Heritage Site on the Sulu Sea about 130 kilometres (80 miles) southeast of the western island of Palawan.
The site is protected by Philippine law, and is off-limits to navigation except for research or tourism approved by Songco's office.
Songco said it was too early to assess the damage to the corals and the corresponding fines, with the vessel still stuck on the reef and being battered by big waves.
The commander of the US Navy's 7th Fleet, Vice Admiral Scott Swift, apologised in a statement from Japan on Sunday.
"As a protector of the sea and a sailor myself, I greatly regret any damage to this incident has caused to the Tubbataha Reef," Swift said.
He acknowledged that protecting the reef was vital, and that the Navy took its obligations to preserve marine environment seriously.
He said the crew members had left the vessel, and there were no traces of any oil leaks.
The Philippine Navy said three of its ships had been put on standby near the area to assist in efforts to remove the Guardian from the reef, to join two civilian tugboats contracted by the Americans.
The Guardian had been en route to Indonesia after visiting a Philippine port north of Manila when the incident occurred, according to the US Navy.
Some politicians and nationalist activist groups have said the US ship had violated the terms of a 1999 visiting forces agreement by sailing in the area.