SEOUL - South Korean President Lee Myung-bak and Chinese President Hu Jintao exchanged messages Friday in celebration of the 20th anniversary of the establishment of diplomatic ties between the two countries.

South Korea and China achieved "remarkable" progress in forging friendly and cooperative relations in just 20 years, Lee said in his letter to Hu, according to the presidential office Cheong Wa Dae.

A free trade agreement between the two countries, if reached, will "open a new horizon" in their relations, Lee added, voicing hope for close cooperation down the road.

Hu also express appreciation of "comprehensive and substantial" progress in China's ties with South Korea, noting the two countries share common interests in strengthening bilateral cooperation and promoting peace in the region and in the world.

The two Asian powerhouses established formal diplomatic relations in 1992.