The government is making arrangements to provide patrol boats and other vessels to Yemen for use in antipiracy operations off the coast of Somalia, sources said Tuesday.

The patrol vessels are equipped with bulletproof glass and other devices that qualify them as "weapons" that would infringe on Japan's ban on arms exports, but the government plans to make an exception in this case, the sources said.

Even though the move is intended to fight piracy against commercial ships, including those serving Japan, some lawmakers may raise concerns that Japan's long-held weapons export ban could be undermined.

It would be the second time Japan has provided such patrol vessels. Three were given to Indonesia. The Cabinet authorized that decision in June 2006.

Giving patrol vessels to Yemen, located opposite Somalia across the Gulf of Aden, will be aimed at boosting its capability to oversee its coastline and nearby waters, the sources said.

They will be financed by using grant aid, and the government will ask Yemen to pledge that the vessels will not be diverted for military use, they said.

Earlier this month, the Japan Coast Guard sent staff to the region to conduct research on the possible impact of such patrol boats, the sources said.

In October, the government invited coast guard officers from Yemen to take part in a training program conducted by the Japan Coast Guard on cracking down on maritime crimes. The government has expressed readiness to cooperate with Yemen in improving its vigilance over the seas.