DUBLIN — A family planning charity plans to open the first abortion clinic on the island of Ireland, challenging decades of legal confusion over the extremely limited access to pregnancy terminations in both parts of the island.

Officials at the Marie Stopes facility due to open next week in Belfast, capital of the British territory of Northern Ireland, said Thursday they plan to offer nonsurgical abortions to women whose pregnancies are less than nine weeks in gestation. They expect protests and have declined to reveal the clinic’s street address.

Women will receive medication that causes a miscarriage only if doctors determine that continued pregnancy would jeopardize their physical or mental health.

Abortions under such circumstances are supposed to be legal already in both parts of Ireland. But lawmakers have failed for decades to clarify the situation, leaving hospitals and doctors fearful of suffering pickets or lawsuits if they are publicly identified as an abortion provider.

In Belfast, Northern Ireland lawmakers have repeatedly bungled the publication of legal guidelines to doctors, while in Dublin, successive Republic of Ireland governments have refused to pass legislation in line with a landmark 1992 Supreme Court judgment. It ordered abortions to be legalized to save a woman’s life — including her own threat to commit suicide if denied one.