Congress acted with just hours to spare Tuesday and gave thousands of illegal immigrants three more weeks to seek legal residence instead of having to leave the country immediately.

The reprieve - through Oct. 23 - was included in a bill keeping federal agencies financed for the start of fiscal 1998, which begins today. The Senate approved the overall measure without debate by 99-0, with only Sen. Patrick Leahy, D-Vt., missing the vote.

President Clinton will sign the bill “whenever we get it,” said White House spokesman Joe Lockhart. The House approved the measure Monday by 355-57.

Final congressional action came as lawyers, charitable organizations and other groups were flooded by thousands of calls from immigrants worried that the grace period was about to expire.

The provision applies only to illegal immigrants who are eligible for legal residence, either because they’re already in line for visas or are the spouse or minor child of a U.S. citizen. Parents of adult children who are U.S. citizens also can apply.