SINGAPORE - The Maritime and Port Authority (MPA) said on Friday (July 5) that it has not received any information on immediate threats to ships heading through the straits of Malacca and Singapore.

There are also no immediate threats to Singapore-registered ships, it said, in response to media queries, days after China raised its security level for vessels passing through the Malacca Strait, which is a key Asian trade route.

"The Port of Singapore will maintain the current security level one as per the International Ship and Port Facility Security (ISPS) Code, and Singapore's security agencies will continue to be vigilant," MPA said.

It added that all ships transiting the straits are advised to be vigilant, and implement security measures according to the ISPS ships security plan, regardless of the security level.

China's Transport Ministry on Tuesday advised Chinese-flagged ships to take heightened security steps and increased its security warning to level three, according to a copy of a notice posted on a website affiliated with the ministry, Bloomberg reported.

This is the highest security level in Chinese shipping regulations, and one above a warning issued after recent attacks on tankers in the Strait of Hormuz, Bloomberg said, citing people familiar with the situation, who asked not to be identified discussing government notifications.

There was no reason given for the raised alert in the Malacca Strait, a stretch of water passing Malaysia, Singapore and Indonesia that connects the Indian and Pacific oceans.

It is second only to the Strait of Hormuz as a key oil and gas conduit, and connects Middle Eastern and African energy supplies to Asian economies.

China has emerged as the world's biggest importer of crude and natural gas, making it increasingly reliant on supplies vulnerable to bottlenecks or disruption.

The warning from China comes after a string of attacks in June on tankers near Hormuz, which the United States blamed on Iran and heightened vigilance across the shipping industry.

The MPA said it will closely monitor the situation and provide updates to ships traversing the Malacca and Singapore straits as well as Singapore-registered ships.