An open letter launched by Baroness O'Loan in opposition to extending abortion to Northern Ireland has been signed over 15,000 times.
The letter to Prime Minister Theresa May says that the changes voted through in Westminster last week would "treat the people of Northern Ireland with contempt".
Baroness O'Loan criticised the fast-track procedure used to pass the amendments instead of the standard parliamentary procedure that would have included a three-month public consultation to allow for scrutiny and debate.
She warned that the turn of events could "undermine the delicate political calibration between Northern Ireland and Westminster" and "cause significant damage to attempts to restore the Northern Ireland Assembly".
The letter concludes with a demand to the Government to either withdraw the Bill or add a clause to address the "democratic deficit".
"The imposition of this legislation on Northern Ireland in its current form, voted for only by MPs who do not represent constituencies in Northern Ireland, would represent a massive democratic deficit," she writes.
MPs in the Commons voted 332 to 99 to give Northern Ireland the same abortion access as the rest of the UK in the event that devolution is not restored by October 21.
The Government had until now resisted pressure to extend abortion laws to the province while Stormont remained suspended over political deadlock.
Baroness O'Loan added: "Regardless, then, of what one thinks about abortion it is a very big issue and the manner in which there has been an attempt to change abortion law in Northern Ireland this week treats the people of Northern Ireland with contempt, since there is this huge democratic deficit in a situation in which sensitive negotiations are ongoing."
The letter has the support of pro-lifers and evangelical Christians. Campaign group Right to Life UK said that the vote in Parliament amounted to an "anti-democratic move by Westminster".
Clare McCarthy, spokeswoman for the Right To Life UK said: "It is disgraceful that the Government would not just allow this hijacked Bill to pass under their watch, but now they intend to introduce secondary legislation to directly introduce abortion on demand to Northern Ireland without any involvement from the people of Northern Ireland.
"This is a shocking departure from the Government's neutral position on abortion and a departure from their firmly-held position of respecting devolution.
Peter Lynas, director of the Evangelical Alliance Northern Ireland, is urging people in Northern Ireland to sign the letter.
"Please don't look back in a few months time with regret and say you didn't realise the moves to bring abortion to NI were serious or you didn't know what to do," he tweeted.
"Read this letter, sign it and make sure we do what we can to keep our life affirming culture."
