A Taiwanese official has asserted that the United States is becoming more “wary” about selling arms to his government, as Chinese reaction to those arm sales gets stronger and stronger.

Taiwan's Deputy Defense Minister Andre Yang made the remark Monday at an annual U.S.-Taiwan defense industry conference in Virginia. His comment followed reports that the Obama administration has told Congress it will upgrade Taiwan's existing fleet of F-16 fighter jets, but will defer a Taiwanese request to sell the island more advanced planes.

The reported cost of the upgrade would be $4.2 billion.

China's official media earlier Monday warned of “severe consequences” if the United States goes ahead with the upgrade plans. The China Daily newspaper said it would provoke a fierce reaction from China, affecting its relations with Taiwan and the United States.

For its part, Taiwan has characterized the United States as yielding to Chinese pressure in reducing the arms package. Deputy Defense Minister Yang said Monday that whatever the outcome of the current F-16 deal, Taiwan plans to continue to push for more sophisticated fighters in the future.

Obama administration officials say they will not comment on the sale until they have formally notified Congress — something that is expected before the end of this month.

U.S. law obliges Washington to sell Taiwan defensive weapons.