Five U.S.-listed Chinese state-owned companies whose audits are under scrutiny by the U.S. securities regulator said on Friday they would voluntarily delist from the New York Stock Exchange.

Oil giant Sinopec and China Life Insurance, Aluminum Corporation of China (Chalco), PetroChina and a separate Sinopec entity, Sinopec Shanghai Petrochemical Co, each said they would apply to delist their American Depository Shares this month. They will keep their listings in Hong Kong and mainland China.

In May, the U.S. Securities and Exchange Commission (SEC) flagged the five companies and many others as failing to meet U.S. auditing standards.The companies did not mention the dispute in their announcements, which come as tensions mounted after U.S. House of Representatives Speaker Nancy Pelosi visited Taiwan.

Beijing and Washington are in talks to resolve a long-running audit dispute which could result in Chinese companies being banned from U.S. exchanges if China does not comply with Washington’s demand for complete access to the books of U.S.-listed Chinese companies.

Beijing bars foreign inspection of audit documents from local accounting firms, citing national security concerns.

U.S.-listed shares of China Life Insurance and oil giant Sinopec fell 3.06% and 3.22% respectively on Friday. Aluminium Corporation of China dropped 3.03%, while PetroChina shed 2.80%. Sinopec Shanghai Petrochemical Co shed 3.29%.