The vessels, scheduled to be delivered to the Coast Guard by October 2025, are aimed at strengthening law enforcement and maritime rescue operations and ensuring security, maritime safety and freedom of navigation in Vietnam, JICA said in a statement.

The 40-year loan has a grace period of 10 years, and the vessels would be built by a Japanese company.

Details about the vessels have not been disclosed.

The South China Sea, known as the East Sea in Vietnam, is severely affected by natural disasters, which pose a high risk of maritime accidents, JICA said.

In recent years smuggling, illegal fishing and the risk of terrorism have increased, and so strengthening maritime capability and safety is one of Vietnam’s key tasks, it said.

Vietnam and some other Southeast Asian countries are locked in maritime disputes in the South China Sea as China claims 90 percent of the potentially energy-rich waters.

China has been ramping up its aggressive behavior in the waters since the start of this year while other countries have been focused on combating the Covid-19 outbreak.

The U.S. earlier this month released statements supporting Southeast Asian nations including Vietnam in their disputes with China at sea.

The statement rejected China's claims to most of the waterway, including waters surrounding Vietnam's Vanguard Bank, Luconia Shoals off Malaysia, waters in Brunei’s EEZ, and Natuna Besar off Indonesia.

Australia last week joined the U.S. in stating that China's claims in the South China Sea do not comply with international law.

Last year the U.S. announced it would provide Vietnam with another coast guard cutter for its growing fleet, in addition to at least 18 "Metal Shark" patrol boats it provided to Vietnam in the last three years to boost its ability to patrol its waters.