SEOUL, Sept 7 (Reuters) - South Korean President Yoon Suk Yeol said on Thursday any attempts to change the status quo by force in the South China Sea cannot be tolerated, calling for a rules-based maritime order in the region, his office said.

Yoon was speaking at the East Asia Summit with the ASEAN bloc, China, the United States and others in Jakarta, Indonesia.

"(Yoon) emphasised the need for the establishment of a rules-based maritime order in the South China Sea, the region's key sea lane," his office said.

Yoon also said North Korea's nuclear programme was a real threat that can target all countries participating at the summit, and stressed the "heavy responsibility" of permanent members of the United Nations Security Council.

The remarks come amid reports North Korean leader Kim Jong Un plans to travel to Russia this month to meet President Vladimir Putin and discuss weapons supplies to Moscow.

The United States has said North Korea would pay a price for supplying Russia with weapons to use in Ukraine. South Korea has said the United Nations member states should not violate sanctions, including through arms deals.