RALEIGH, N.C. (AP) — North Carolina’s Democratic governor will veto legislation Saturday that would ban nearly all abortions after 12 weeks of pregnancy, capping a week of attempting to generate enough opposition to block the Republican measure he said is much more restrictive than meets the eye.

Abortion-rights activists plan to gather on a plaza in Raleigh near Gov. Roy Cooper's office and the Legislative Building to see him veto the bill, which also would place additional duties upon physicians, abortion clinics and the women seeking the procedure.

The veto will launch a major test for leaders of the GOP-controlled General Assembly to attempt an override vote after they recently gained veto-proof majorities in both chambers.

Cooper, a strong abortion-rights supporter, has until Sunday night to act on the measure that would tighten current state law that bans abortions after 20 weeks of pregnancy. Override voting could begin next week.

Party-line votes for passage last week in the House and Senate signaled Cooper’s expected veto could block the bill’s enactment if just one Republican who voted yes changes their mind or is absent during an override vote. So the governor spent this week on the road talking about the bill’s lesser-known details and urging residents to apply pressure upon key Republican lawmakers who expressed hesitance about further restrictions during their campaigns for office last year.

Republicans have pitched the measure as a middle-ground change to state abortion laws developed after months of private negotiations between House and Senate GOP members. It adds exceptions to the 12-week ban, extending the limit through 20 weeks for rape and incest and through 24 weeks for “life-limiting” fetal anomalies.

But Cooper has said repeatedly the details contained in the 47-page bill show that the measure isn’t a reasonable compromise and would instead greatly erode reproductive rights.