FILE PHOTO: A Police Coast Guard vessel patrols the shipping lanes near freight ships off the coast of Singapore, partof the Malacca Strait, March 4, 2010. REUTERS/Vivek Prakash/File Photo

BEIJING (Reuters) - China’s Ministry of Transport has raised the security level for Chinese vessels in the Malacca Strait, a major bottleneck for global oil trade, according to a notice dated July 2 that was sent to ship brokers.

The level for Chinese vessels passing through and going to the strait was raised to 3, the highest in the three-tier system, as of 10 p.m. local time on July 2 (0200 GMT), according to the notice, whose authenticity was confirmed by an official at the ministry.