BEIJING, Sept 5 (Reuters) - China's top security agency has hinted that any meeting between President Xi Jinping and U.S. President Joe Biden in San Francisco later this year will depend on the United States "showing sufficient sincerity".

Biden on Sunday expressed disappointment that Xi was not attending an upcoming summit of G20 leaders in India, but added that he was going to "get to see him".

Biden did not elaborate but the next likely opportunity for Biden to hold talks with Xi, as the two countries seek to stabilise troubled relations, is an Asia-Pacific Economic Cooperation (APEC) summit in San Francisco in November.

"To truly realise 'from Bali to San Francisco', the United States needs to show enough sincerity", the Ministry of State Security said in a post on Monday on its WeChat social media page.

It was referring to the last meeting between Biden and Xi on the sidelines of a G20 summit on Indonesia's resort island of Bali in November last year. It did not mention the APEC summit in its post.

It is unclear if the ministry, which is China's main intelligence agency, is privy to, or has influence over, Xi's considerations on diplomatic engagements.

This weekend, Premier Li Qiang will lead a delegation to a G20 summit in New Delhi, the Chinese government has announced, all but confirming that Xi would not attend.

The ministry in its post said Biden's administration had adopted a dual-natured strategy towards China, inviting competition with China but also wanting to control the competition.

It said while U.S. officials who visited China recently said there was no intention to curb China's development or "decouple", the U.S. still approved arms sales and provided military financing to Taiwan, and raised issues about Tibet and the South China Sea as well as openly criticising the Chinese economy.

"China will never let its guard down because of a few 'nice words' from the United States ... The various obstacles, containment and suppression by the United States will only make China more courageous and self-reliant," the state security ministry said.

U.S. Commerce Secretary Gina Raimondo, who visited China last week, said the United States did not want to decouple from China but she also said U.S. companies had complained to her that China has become "uninvestible," pointing to fines, raids and other actions that have made it risky to do business in the world's second-largest economy.

China repeated calls for the United States to take more "practical and beneficial actions" to maintain China-U.S. ties after the "uninvestible" comment was reported.