Despite China's best efforts to avoid the South China Sea issuing from overshadowing a regional summit, Southeast Asian leaders raised their concerns over the maritime dispute yesterday. Speaking at a summit between China and the Association of South East Asian Countries (Asean), which is among a series of annual meetings taking place in Kuala Lumpur this weekend, Premier Li Keqiang said Beijing's ties with the 10-nation grouping had improved "steadily" over the past year. "China has always made relations with Asean a priority," Li said. The past year saw heightened regional tensions over Beijing's island reclamation projects in the intensely contested South China Sea, which pits China against South East Asian countries including Vietnam, Malaysia, the Philippines and Brunei. The annual summits, which involve Asean and powers including the United States, China and Japan, have been used as a platform to raise the issue with China. But Beijing has disregarded Asean's role in resolving the territorial disputes and prefers to deal with claimants bilaterally. Much to Beijing's chagrin, the leaders have expressed concerns in joint statements at the end of the event for many years. Before the summits, Chinese officials have said the event should not be used to discuss the maritime territorial issues. Speaking at the Asean opening ceremony yesterday, Malaysian Prime Minister Najib Razak urged "all parties" to exercise self-restraint and to avoid escalating tension in the South China Sea, without naming the countries. At a meeting with Asean leaders, US President Barack Obama said claimants should avoid militarising the issue and slow down the building of artificial islands. The US, itself not a claimant, has criticised China's island building as destabilising the region. To send its message, Washington recently sent the guided missile destroyer USS Lassen to sail through waters within 12 nautical miles of Subi Reef, originally a feature that was submerged at high tide but has been reclaimed into a bigger island. The Washington Free Beacon reported on Friday that the US would send two warships on a similar operation to sail by another disputed island in the Spratlys, Mischief Reef. Meanwhile, in a meeting with Australian Prime Minister Malcolm Turnbull, Li said Beijing would contribute US$14.5 million to the search for missing Malaysian Airlines flight MH370. The plane vanished in March, 2014, on a flight from Kuala Lumpur to Beijing with 239 mostly Chinese passengers and crew.