Japanese Prime Minister Shinzo Abe said on Friday that Tokyo would provide Southeast Asian nations its "utmost support" in their territorial disputes over the South China Sea, in a speech that received a hostile response from China.

In the South China Sea, scores of Vietnamese and Chinese ships, including coastguard vessels, have continued to square off around a Chinese oil rig in contested waters.

Tensions heightened last week when Hanoi said a Chinese boat rammed and sank a Vietnamese fishing vessel not far from the oil rig. China's official Xinhua news agency reported the vessel capsized after "harassing and colliding with" a Chinese fishing boat.

Vietnam Vice Defence Minister Nguyen Chi Vinh told Reuters on Sunday Japan, itself locked in a bitter territorial spat with China, was helping it to train its coastguard and share information with its teams, as well as sending some vessels.

"The process is developing very well and we are planning to receive the ships by early next year," Vinh said in an interview on the sidelines of the Shangri-La Dialogue in Singapore, Asia's biggest security forum.

Abe had told parliament on Wednesday that Japan was unable to immediately provide decommissioned patrol ships to Vietnam as its own coastguard was stretched by surveillance activities.

Patrol ships from China and Japan have been playing cat and mouse in waters near disputed East China Sea islets, raising fears of an accidental clash between the world's second- and third-largest economies.

Vietnam urges others to speak up

Vinh said that while he welcomed the support of Japan and the United States he believed other nations could be more vocal about China's actions in the South China Sea.

"I have the feeling that every country, whether they publicly state it or not, realize the wrongdoing of China and do not agree with what they are doing," he said.

"I feel that other countries must raise their voice stronger, in a more public way."

Some Southeast Asian nations such as Malaysia have remained wary of speaking out against China for fear of damaging deep-rooted economic ties.

The United States and China squared off at the security forum in Singapore on Saturday, with the U.S. defense secretary accusing Beijing of destabilizing the region and a top Chinese general retorting that his comments were a "threat and intimidation".

Vinh said he met with Wang Guanzhong, deputy chief of the People's Liberation Army, who stuck to China's "previously stated perspective".

"I told their deputy chief of general staff that Vietnam never wants to have tension with China," he said.

"We do not want to fight to get a winner or loser with them, what we want is peace and territorial sovereignty and integrity."

By Rachel Armstrong - Reuters - June 1st, 2014