Marie Stopes, the sexual health charity, predicts women will travel to Belfast from the Republic to have terminations when it opens the first private clinic to offer abortions on the island of Ireland.

Northern Ireland is the only part of the UK where the Abortion Act 1967 does not apply, owing to opposition from the churches and almost all parties at the Stormont assembly, and abortion is legal only in exceptional circumstances. Like their counterparts in the Republic, where abortions are illegal, Northern Irish women travel to other parts of Britain for terminations.

The centre's programme director, Dawn Purvis, said: "We believe this is great news for the people of Northern Ireland because we will be able to meet their family planning and sexual health needs in a way that has not been seen here before. We have a new, purpose-built, centrally located specialist centre. Our team are highly trained and dedicated healthcare professionals. And our services will be delivered in a confidential, sensitive and non-judgmental way."

Purvis is a former leader of the Progressive Unionist party.

Abortions will only be offered in the first nine weeks of pregnancy at a cost of £450. The clinic, which opens next Thursday, also provides sexual and reproductive services including short- and long-term contraceptive options, emergency contraception and HIV testing.

Dr Paula Franklin, medical director with Marie Stopes, said the abortions, which involve taking tablets, would be carried out only after two doctors agreed women met set criteria.

"In cases where we feel the woman's case meets medical requirements, we will carry out medical abortions. That's where two doctors independently review the woman's history and current physical and mental health," she said.

Sinéad Ahern, a spokeswoman for Choice Ireland, a pro-choice organisation in the Republic, said it would reduce the "psychological and financial burden" on women south of the border seeking a termination.

Anti-abortion campaigners in Northern Ireland say they will campaign to close down the clinic offering abortion services. Bernie Smith from the organisation Precious Life said: "I am absolutely outraged. An organisation which is making profits from the death of unborn children is not welcome in Northern Ireland. There will be an outcry from the people, from government and from the churches."

A group of Irish nationals who had abortions abroad because their babies would not survive outside the womb also welcomed the opening of the clinic in Belfast.

But Ruth Bowie, of the Terminations for Medical Reasons campaign group, said a number of women both sides of the border would still be forced to cross the Irish Sea to have a termination. Fatal foetal abnormalities are only picked up within 12 to 20 weeks of pregnancy – long after the nine-week limit at the Marie Stopes clinic in Belfast.

"This development in Belfast will be of no help to the women north and south who are facing the trauma and upset of fatal foetal abnormalities," Bowie said. "Women and men in this situation continue to be forced to travel away from family, friends and their homes at the worst time of their lives.

"We continue to campaign for a change in this outdated law and will not stop until women and men who make this heartbreaking decision are afforded to the dignity to be cared for in their own country."