The State Department is proposing requiring applicants for business and tourist visas to post a bond of up to $15,000 to enter the United States, a move that may make the process unaffordable for many.

In a notice to be published in the Federal Register on Tuesday, the department said it would start a 12-month pilot program under which people from countries deemed to have high overstay rates and deficient internal document security controls could be required to post bonds of $5,000, $10,000 or $15,000 when they apply for a visa.

The proposal comes as the Trump administration is tightening requirements for visa applicants. Last week, the State Department announced that many visa renewal applicants would have to submit to an additional in-person interview, something that was not required in the past. In addition, the department is proposing that applicants for the Visa Diversity Lottery program have valid passports from their country of citizenship.

A preview of the bond notice, which was posted on the Federal Register website on Monday, said the pilot program would take effect within 15 days of its formal publication and is necessary to ensure that the U.S. government is not financially liable if a visitor does not comply with the terms of his or her visa.

“Aliens applying for visas as temporary visitors for business or pleasure and who are nationals of countries identified by the department as having high visa overstay rates, where screening and vetting information is deemed deficient, or offering citizenship by investment, if the alien obtained citizenship with no residency requirement, may be subject to the pilot program,” the notice said.

The countries affected will be listed once the program takes effect, it said. The bond could be waived depending on an applicant’s individual circumstances.

The bond would not apply to citizens of countries enrolled in the Visa Waiver Program, which enables travel for business or tourism for up to 90 days.

The majority of the 42 countries enrolled in the program are in Europe, with others in Asia, the Middle East and elsewhere.

Visa bonds have been proposed in the past but have not been implemented. The State Department has traditionally discouraged the requirement because of the cumbersome process of posting and discharging a bond and because of possible misperceptions by the public.

However, the department said that the previous view “is not supported by any recent examples or evidence, as visa bonds have not generally been required in any recent period.”