The US Navy defended the timing of joint military exercises with Vietnam at their opening ceremony Friday after criticism from Beijing, dpa reported. The event has nothing to do with territorial disputes in the South China Sea and there is "nothing unusual or provocative about it," Rear Admiral Thomas Carney said at a meeting to kick off the seven-day manoeuvres in Da Nang, a popular tourist destination on Vietnam's central coast. "I don't know when an appropriate time would be for these kinds of activities, which are designed to promote friendship and cooperation, but I don't think there is ever a bad time to do those kinds of activities," he said. The joint exercises focus on non-combat drills and skills exchanges, including navigation and maintenance. There are also to be a medical and dental exchange. The chief of staff of China's People's Liberation Army, Chen Bingde, was quoted Monday by state media as saying the timing of the naval activities was "inappropriate" given tensions over territory in the region. The resource-rich South China Sea is partially claimed by several Asian states, including Vietnam and the Philippines, which have been receiving US support for their claims, but China insisted that it has sovereignty over disputed islands and surrounding waters. Tensions have risen in recent weeks after Vietnam accused China of harassing seismic survey ships and fishing boats in the contested area while Beijing alleged that Vietnamese boats had entered its waters illegally and endangered Chinese fishermen. Despite the commencement of talks between the two countries after a visit to Beijing by Vietnamese Deputy Foreign Minister Ho Xuan Son on June 26, state media in Vietnam on Thursday reported further harassment of fishermen near the Paracel Islands. According to an article in the Ho Chi Minh City-based newspaper Phap Luat, Chinese soldiers boarded a Vietnamese fishing boat on July 5, beat the captain and confiscated a ton of fish. -- SPA