Beijing - China on Friday praised the leaders of North and South Korea for their political "courage" and welcomed their joint declaration vowing to denuclearise the Korean peninsula and seek a peace treaty.The foreign ministry called the handshake between North Korean leader Kim Jong Un and the South's President Moon Jae-in over the Military Demarcation Line that divides the peninsula a "historic moment"."We applaud the Korean leaders' historic step and appreciate their political decisions and courage," foreign ministry spokeswoman Hua Chunying told a regular press briefing."We hope and look forward to them taking this opportunity to further open a new journey of long-term stability on the peninsula."She also cited a poem that reads: "We remain brothers after all the vicissitudes; let's forgo our old grudges, smiling we meet again."China is North Korea's sole major ally, having fought by its side in the 1950-1953 Korean War. But Beijing has supported a series of United Nations sanctions to punish Pyongyang over its nuclear and missile tests.Relations have chilled but Kim held talks with Chinese President Xi Jinping in a surprise meeting in Beijing in March, his first official trip abroad.Beijing has pressed for dialogue to peacefully resolve the nuclear crisis.Another foreign ministry spokesman, Lu Kang, issued a statement late Friday following the signing of the joint declaration by Kim and Moon, calling it "an important consensus".The two leaders issued a statement confirming their goal of "complete denuclearisation".They also agreed to seek a permanent end to the Korean War this year, 65 years after hostilities ended in an armistice rather than a peace treaty.In the declaration, the two sides said they would seek meetings this year with the US and possibly China -- both parties to the 1953 ceasefire - "with a view to declaring an end to the war, turning the armistice into a peace treaty, and establishing a permanent and solid peace regime".Lu said China "welcomes it and extends its congratulations"."The DPRK and the ROK belong to the same nation," Lu added, using the acronyms for the official names of the two Koreas."We hope that the relevant parties will maintain the momentum for dialogue and work together to promote the denuclearisation of the Peninsula and the political settlement process... China stands ready to continue to play its positive role to this end."