Brian Hook, State Department director of policy planning and head of a special action group on Iran created this week, told a press conference on Thursday that China will not be exempt from penalties if it continues buying Iranian oil after the second, and much more strict, rounds of renewed U.S. sanctions on Iran go into effect in November.

A reporter at the press conference noted that China has indicated it will continue purchasing Iranian oil, and might even increase its imports.

Asked what the United States will do if China insists on defying U.S. sanctions, Hook responded:

Our goal is to reduce every country’s import of Iranian oil to zero by November 4th, and we are prepared to work with countries that are reducing their imports on a case-by-case basis. As you know, those sanctions will come into effect on November 5th. Those will include sanctions on Iran’s energy sector, transactions by foreign financial institutions with the Central Bank of Iran, Iran’s shipping and shipbuilding sectors, among others. And the United States certainly hopes for full compliance by all nations in terms of not risking the threat of U.S. secondary sanctions if they continue with those transactions.

“We are prepared to impose secondary sanctions on regimes—I’m sorry, on other governments that continue this sort of trade with Iran,” Hook clarified.

The Wall Street Journal noted on Thursday that while China imports over a quarter of Iran’s oil, friendlier nations such as India and South Korea are also top customers.

India and South Korea are among the nations that have already begun scaling back Iranian oil purchases in preparation for the November sanctions, which can only be averted in the seemingly unlikely event Tehran satisfies a list of 12 conditions laid out by U.S. Secretary of State Mike Pompeo in May.

The Iran Action Group headed by Brian Hook is tasked with coordinating Iran policy and keeping U.S. allies on board, an objective likely to become increasingly difficult as oil sanctions fall into place.