Vietnamese authorities are demanding a halt to weekly demonstrations in the capital against China, saying unidentified “opposing forces” are using them to undermine social order and stability.

The Hanoi People's Committee ordered the halt in a broadcast Thursday, warning the government will apply “necessary measures” against those who fail to comply.

Demonstrators have turned out in Hanoi every Sunday for about 10 weeks to protest Chinese actions in the South China Sea. The government says Chinese vessels have deliberately interfered with oil exploration activities in disputed waters off its shores.

In most cases, police simply watched the protests, suggesting authorities approved of the action. But the demonstrations were broken up on a few occasions while the government was conducting delicate negotiations with China on the issue.

Thursday's announcement described the protests as spontaneous and acknowledged they are motivated by patriotism. But it said they are adversely affecting social order and the city's image while negatively impacting diplomatic activities of the ruling party and state.

The announcement charged that in recent days, opposing forces within and outside the country have been inciting and guiding the demonstrations. It demanded that the participants stop all activities and gatherings in the city.