WASHINGTON, Aug 6 (Reuters) - U.S. Secretary of State Antony Blinken expressed deep concern about China"s growing nuclear arsenal during a meeting with foreign ministers of Asian countries and partner nations, the State Department said on Friday. Addressing a virtual meeting of the ASEAN Regional Forum (ARF), which groups more than two dozen countries, Blinken also called on China to cease "provocative" behavior in the South China Sea and "raised serious concerns about ongoing human rights abuses in Tibet, Hong Kong, and Xinjiang," the department said in a statement. "The Secretary also noted deep concern with the rapid growth of the PRC’s nuclear arsenal which highlights how Beijing has sharply deviated from its decades-old nuclear strategy based on minimum deterrence," it added, using the acronym for China"s official name, the People"s Republic of China. In his address, Blinken urged all ARF member states to press Myanmar"s military government to end violence and support the people of the country as they work to return to democratic governance, the statement said. Both the Pentagon and State Department have aired concerns recently about China"s buildup of its nuclear forces following think-tank reports based on satellite imagery saying that China appears to be constructing hundreds of new silos for nuclear missiles. read more Washington has repeatedly called on China to join it and Russia in a new arms control treaty and last month the State Department urged Beijing to engage with it "on practical measures to reduce the risks of destabilizing arms races." read more A 2020 Pentagon report estimated China"s nuclear warhead stockpile in "the low 200s" and said it was projected to at least double in size as Beijing expands and modernizes its forces. Analysts say the United States has around 3,800 warheads, and according to a State Department factsheet, 1,357 of those were deployed as of March 1. Beijing says its arsenal is dwarfed by those of the United States and Russia and it is ready to conduct bilateral dialogues on strategic security "on the basis of equality and mutual respect." read more Blinken has taken part in a series of regional meetings this week at which he has sought to reinforce the U.S. message that it is serious about engaging with Asian countries to push back against Beijing. read more