The U.S. - China relationship seems to have soured significantly since the two nations announces the "Phase 1" trade deal in January. Since then, China has yet to meet its commitments under the agreement, and President Trump has largely placed blame of the pandemic on China for failing to appropriately contain the outbreak, which originated in the Wuhan province of China late in 2019. President Trump has expanded upon his statements against China in recent weeks, and tensions in Hong Kong have also escalated, thus adding to the strain between the two nations.
More below:
https://www.cnbc.com/video/2020/05/28/trump-will-hold-press-conference-on-china-tomorrow.html
https://www.washingtonpost.com/business/2020/05/27/trump-china-hong-kong-trade/
https://www.politico.com/newsletters/politico-china-watcher