The Philippines and Vietnam, two of the most vocal critics of China's attempts to claim almost all of the South China Sea, have held talks on forging a strategic partnership, an official said Tuesday.

Without naming China directly, Philippines foreign department spokesman Charles Jose said the talks focused on issues of mutual concern and singled out the South China Sea issue, a territorial dispute involving several countries in the region.

He said the talks were held last week and involved Philippine Foreign Secretary Albert del Rosario and Vietnamese Foreign Minister Pham Binh Minh.

"It is important because we share common concerns in this region especially when it comes to the South China Sea issue," he told reporters.

He described the issue as "one of the moving forces," behind the planned partnership.

The Philippines and Vietnam have been the most outspoken countries in the region in criticising China's efforts to claim virtually all of the South China Sea, which contains major sea lanes and fishing grounds and is believed to hold vast mineral resources.

Brunei, Malaysia and Taiwan also have conflicting claims to the waters.

The Philippines and Vietnam have in recent years accused China of increasingly flexing its military muscle in the region.

This has included the deployment of a Chinese oil rig to the north of the Spratlys which raised tensions with Vietnam last year.

Jose said "discussions are still ongoing but both sides agreed to elevate the relations to a higher level".

He stressed that "security and defence" were part of the partnership but that it would also cover economic and trade issues.

The Philippines presently has strategic partnerships with the United States and Japan, he added.

Last month, del Rosario said he would warn fellow members of the Association of Southeast Asian Nations (ASEAN), including Vietnam, Brunei and Malaysia, that China's efforts in the region were a threat to all of them.

China's official news agency in turn, on likened the Philippines to a "crying baby" for seeking such international support against its actions in disputed waters.