White House national security adviser Jake Sullivan met with Chinese Foreign Minister Wang Yi in Malta this weekend, according to reports from Beijing and Washington on Sunday, as the world’s two largest economies sought to repair strained ties.

According to separate statements issued Sunday by the White House and the Chinese Foreign Ministry, both parties engaged “candid, substantive, and constructive” conversations over various sessions held Sept. 16-17.

Sullivan’s meeting with Wang was the latest in a series of high-level meetings between US and Chinese officials, which might pave the way for a meeting between US President Joe Biden and Chinese President Xi Jinping later this year.

Sullivan last saw Wang in May in Vienna.

China’s foreign ministry said both sides agreed to maintain high-level exchanges and hold bilateral consultations on Asia-Pacific affairs, maritime affairs and foreign policy.

The White House added that both sides “committed to maintain this strategic channel of communication and to pursue additional high-level engagement and consultations in key areas … in the coming months”.

Washington said Sullivan “noted the importance of peace and stability across the Taiwan Strait”, while Wang cautioned the United States that the Taiwan issue is the “first insurmountable red line of Sino-U.S. relations”, according to the Chinese foreign ministry statement.

Biden this month expressed disappointment that Xi skipped a summit of Group of 20 leaders in India, but said he would “get to see him.” The next likely opportunity for Biden to hold talks with Xi is an Asia-Pacific Economic Cooperation (APEC) summit in San Francisco in November.

U.S. Commerce Secretary Gina Raimondo, Secretary of State Antony Blinken and Treasury Secretary Janet Yellen have traveled to China this year to ensure continued communication between the two countries amid tensions that flared after the U.S. military shot down a Chinese surveillance balloon that traveled over the United States.

Biden and Xi last met in 2022 on the sidelines of a G20 summit on Indonesia’s resort island of Bali.