New U.S. tariff rates are “pretty much set” with little immediate room for negotiation, Donald Trump’s trade advisor said in remarks aired Sunday, also defending the president’s politically driven levies against Brazil.

The tariffs are a substantial new source of revenue for the federal government. The budget may start to depend on it.

Ahead of a Friday deadline, Trump set rates including a 35% duty on many goods from Canada, 50% for Brazil, 25% for India, 20% for Taiwan and 39% for Switzerland, according to a presidential executive order.