The debate on an amendment to outlaw private abortion services in Northern Ireland has got under way in the Stormont assembly.

Assembly members are discussing the proposal from the Social Democrat and Labour party's Alban Maginness and the Democratic Unionist Paul Girvan.

Sinn Féin, the Alliance party and the Green party are opposing the amendment and have put forward a petition of concern to sink the proposed legislation.

If the Maginness-Girvan amendment is voted through, the assembly it could end up closing down non-surgical abortion services offered by the Marie Stopes clinic, which opened last autumn in central Belfast.

At the weekend more than 100 women openly defied the law in Northern Ireland when they revealed in the Observer that they had used abortion pills bought from pro-choice charities over the internet. They have challenged lawmakers and anti-abortion politicians in the province to prosecute them under the 1861 Offences Against the Person Act, which is still on the statute books in Northern Ireland and makes carrying out an abortion a criminal offence liable to life imprisonment.

Opening the debate, the Democratic Unionist minister Arlene Foster condemned Sinn Féin's stance and claimed the party was ideologically bankrupt.

"We have known for some time that Sinn Féin is morally bankrupt in everything that they have been involved in over the past 40 years, but I think that what we have here is an example that they are ideologically bankrupt," she said.