China and the Philippines remain embroiled in a weeklong standoff over a shoal both nations lay claim to in the South China Sea.

Philippine media say the nation's Foreign Ministry lodged a second protest against China on Monday, claiming a Philippine yacht conducting research around the Scarborough Shoal was forced to leave after being harassed by a Chinese aircraft and ship.

The Philippine Foreign Ministry called in the Chinese ambassador to Manila and demanded the standoff be ended so the Philippine ship can complete its research.

But Chinese Foreign Ministry spokesman Liu Weimin responded by calling on the Philippine ship to immediately leave South China Sea, reiterating China’s sovereignty over the region.

The standoff broke out on April tenth when a Philippine warship was prevented by Chinese ships from arresting Chinese fishermen accused of operating illegally in the area.