A decades-long dispute between China and Russia is finally ended as the two countries yesterday unveiled boundary markers for the eastern section of their border at a ceremony held on Heixiazi Island.

After the ceremony, Chinese soldiers started patrolling the 174 sq km of returned territory, or about half of the island (known as Bolshoi Ussuriysky Island in Russia).

Zhao Xidi, an ambassador-level official at the Foreign Ministry, and Vladimir Malyshev, the Russian Foreign Ministry First Asian Department deputy director, jointly unveiled the boundary markers.

Representatives from the two countries' departments of foreign affairs, national defense and public security as well as regional officials were also present.

The foreign ministries of the two countries announced that the additional protocol on the eastern section of the China-Russia Border as well as its appendix have officially taken effect, marking the settlement of the border issue.

"The experience of China and Russia in resolving border disputes left by historical reasons proves that peaceful dialogue and fair and reasonable consultation on an equal basis are effective," Foreign Ministry spokesman Qin Gang told a press conference in Beijing.

He added the resolution set an example for other countries to settle "sensitive" and "complicated" issues.

Qin said the settlement was based on existing bilateral treaties and complied with international law and norms.

"(The settlement) is a result of years-long negotiations and a concrete step forward in the Sino-Russian Good-Neighborly Treaty."

The two countries reached the final agreement for the return of the territory in July during Russian Foreign Minister Sergey Lavrov's visit to Beijing. The agreement officially marked the end of demarcation of the 4,300-km Sino-Russian border.

The 300-sq-km Heixiazi Island is located at the confluence of the Heilongjiang and Wusulijiang rivers that serve as a natural border between China and Russia. It was occupied by the former Soviet Union during a 1929 border skirmish.

After being returned to China, the largely uninhabited territory is expected to become a hotspot for tourism and economic development.

Discussions on building a railway that will connect the island with the mainland are already under way and real-estate investors are eyeing the territory for its development potential.

Given its geographic significance and transportation advantage, a proposal to develop the area into a Northeast Asia free trade zone is also under consideration.