Vietnam and China have seen a breakthrough in their escalating tensions over the South China Sea.

At one point the imbroglio threatened to break out into armed conflict.

But the two Communist nations just finished a two-day joint navy patrol in the Gulf of Tonkin, including a port call to China.

The face-off started late last month, when Chinese ships cut the cords on PetroVietnam's survey ships, which was surveying the South China Sea for oil. In a subsequent attack on June 9, a Chinese vessel cut cords on another PetroVietnam ship, in what Vietnamese Foreign Minister Nguyen Phuong Nga said was a premeditated offensive.

Both countries believe that the other's presence in the South China Sea is an impediment to their national sovereignty.

Why are they after a small piece of water space?

Some Chinese sources estimate the South China Sea holds over 200 billion barrels of oil, roughly 80 percent of Saudi Arabia's total oil reserves, but others say that's an extreme exaggeration.

The sea is also believed to be rich in natural gasses and is one of the most busy shipping routes in the world.

Talks are still underway, but analysts believe that the recent naval patrol represents a gesture -- on the part of both Beijing and Hanoi -- to ease tensions and avoid what could be a costly armed conflict.