A mother faces deportation on Friday after the Home Office rejected new evidence that suggested her young daughters were at risk of having female genital mutilation performed on them in her native Nigeria.

More than 100,000 people have signed a petition calling on the Home Office to halt the planned deportation of Afusat Saliu, 31.

But despite attempts to mount a last-minute legal challenge, and the strength of public support for Saliu – herself a victim of FGM – the Home Office appears determined to force her to return to Nigeria with her daughters, aged one and three.

Saliu, who lives in Leeds, has been ordered to report to Heathrow for deportation on Friday, having exhausted her legal efforts to fight against removal.

It is likely if she does not comply that she and her children, one of whom was born in the UK, will be taken into a refugee holding centre within the next two weeks.

The Home Office on Wednesday rejected new evidence presented by Saliu’s legal team from her former boyfriend and her cousin, who testified that her daughters would be subjected to FGM if the family were deported to Nigeria.

A leading international lawyer, Felicity Gerry QC, had hoped to halt the move with an emergency injunction and a judicial review, but that proved to be impossible for legal reasons.

As the countdown to Saliu's deportation began, George Mudie, the MP for Leeds East, wrote to James Brokenshire, the Home Office minister, calling for the deportation plans to be halted.

Speaking from Leeds, Saliu said she wanted to protect her daughters from suffering the mutilation she had suffered.

She said: “I don’t want my daughters to be mutilated like I was. That will happen if I take them back, I know it because it is the culture of my family. They believe in it and I will not be able to do anything.

“It happened to me and I don’t want my daughters to go through the same thing.”

The campaign backing Saliu’s right to remain in the UK has grown rapidly over the past 48 hours, with the number of people signing a petition on change.org/afusat exceeding 100,000 by Thursday afternoon.

Saliu, who has been supported by friends in Leeds, in particular by Anj Handa, who lodged the petition, said she was overwhelmed by the support of friends and members of the public who did not know her.

“I am so happy for this support. It has made me stronger and it has given me hope.”

Saliu said: “Every woman should stand up for her children and do whatever is necessary to protect them from something like this.”

Saliu said she fled Nigeria in 2011 after her stepmother told her she would get her oldest daughter, Bassy, cut. She says her parents were also forcing her to marry a man 40 years her senior, who she believed also posed a risk to her children.

She first applied for asylum in 2012 but it was denied. An appeal has been dismissed and her recent application to the Home Office presenting new evidence was rejected on Wednesday.

Leeds North West MP Greg Mulholland and the campaigner against FGM Leyla Hussein, have also both backed her fight against deportation.

Mulholland said: “I was very concerned to hear about the treatment that Ms Saliu has received from the Home Office, and I have written to the [UK Border Agency] and requested that they urgently investigate Ms Saliu’s case and ensure that the deportation is put on hold until the matter has been thoroughly looked at again and to allow Afusat and her supporters to submit fresh evidence about the problems she and her children would face if they are returned to Nigeria.

“It is extremely worrying that the Home Office are trying to deport her to Nigeria, despite the threat of violence she faces, and the threat of FGM to her two young daughters, which sadly Afusat has already been a victim of.” The Home Office indicated the deportation would go ahead. While the Guardian was filming Saliu she received a phone call saying she would be deported on Friday. Saliu’s supporters indicated that she would abide by the legal process and make her way to Heathrow.

A Home Office spokesman said: “The UK has a proud history of granting asylum to those who need our protection and we consider every claim for asylum on its individual merits. We believe that those who fail to establish a genuine fear of persecution should return home voluntarily. If they do not, we will enforce their removal.”

•Credit (except headline): The Guardian of London. Photo shows Afusat Saliu.

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