A cross-party group of MPs, campaigners and academics are calling on the government to extend its new domestic abuse legislation to Northern Ireland.
The government's draft domestic abuse bill includes new measures, such as banning abusers from cross-examining victims in family courts.
It also recognises other forms of coercive abuse, such as controlling a victim's finances.
But the bill will not apply to Northern Ireland.
A letter from the Labour Party MP, Stella Creasy, states that the legislation fails to protect all women equally and that women in Northern Ireland are denied "basic rights".
"Without action, this bill risks leaving behind many," she said.
"We want legislation that protects the rights of every woman everywhere in the UK," Ms Creasy told the BBC, adding that she believes women in Northern Ireland are denied "basic rights".
There had been plans for an amendment to the domestic abuse bill, with the aim of liberalising abortion laws in Northern Ireland, the only part of the UK with a near-total ban on terminations.
But the bill was published with provisions only for England and Wales.
Ms Creasy has accused the government of restricting the bill's scope "to avoid upsetting Northern Ireland's Democratic Unionist Party (DUP)", which is opposed to abortion and on which the government relies for a majority in Parliament.
The broadcaster, Sandi Toksvig, human rights organisation Amnesty International and the charity Women's Aid are among 70 organisations and individuals that have added their names to Ms Creasy's letter.
It has also been signed by MPs from the Labour Party, the Liberal Democrats, the Conservative Party, Plaid Cymru and the Green Party.
As well as calling for the government to rethink its decision to restrict the domestic abuse bill to England and Wales, the letter also asks for measures to protect migrant women who are victims of abuse, and may risk deportation if they are dependent on their partner for their visa.
'Significant gap in legislation'
Ms Creasy said: "The UK risks reneging on human rights obligations, whether migrant women or those in Northern Ireland. It risks protections for vulnerable people for the sake of party political gain."
A Home Office spokesperson said that "through the landmark domestic abuse bill the government is transforming the response to this devastating crime and going further to support victims and pursue perpetrators".
The spokesperson added that the Home Office is in discussion with the Northern Ireland Department of Justice about whether it wished to extend any of the bill's provisions to Northern Ireland.
In another letter seen by the BBC, the most senior civil servant in Northern Ireland's Department for Justice, Peter May, also called for Westminster to explore ways to strengthen domestic abuse laws in the region, writing: "We have a significant gap in our legislation."
Northern Ireland has not been able to pass new laws for more than two years since the Stormont assembly collapsed in a bitter split between the DUP and Sinn Féin.
The Attorney General of Northern Ireland, John Larkin, has issued domestic abuse guidance for police and prosecutors on coercive control and stalking.