The IRS has resumed a program under which the U.S. State Department can revoke taxpayers’ passports. Having a “seriously delinquent tax debt” is (unless an exception applies) grounds for denial, revocation or limitation of a passport.

If the IRS determines a taxpayer has a seriously delinquent tax debt, it will “certify” that debt to the U.S. State Department. Previously, the IRS announced it was delaying new certifications and that existing certifications would remain in place unless a taxpayer’s situation changed.

But now the program has resumed. Affected taxpayers will receive notices and must pay what they owe or enter into an agreement with the IRS to avoid jeopardizing their passports.