White House hawks earlier this year encouraged President Donald Trump to stop providing student visas to Chinese nationals, but the proposal was shelved over concerns about its economic and diplomatic impact.

As the administration debated ways to tackle Chinese espionage, Stephen Miller, a White House aide who has been pivotal in developing the administration’s hardline immigration policies, pushed the president and other officials to make it impossible for Chinese citizens to study in the US, according to three people familiar with the situation.

The debate about Chinese students intensified after the White House in December released its national security strategy, which said it would “review visa procedures to reduce economic theft by non-traditional intelligence collectors” and consider restrictions on foreign students in science-related fields.