Theresa May faces pressure to reform Northern Ireland’s abortion laws after the Irish referendum overwhelmingly backed reform.

Two-thirds of voters in Ireland backed reform, leading to calls for an end to the “anomalous” situation in Northern Ireland.

But the Prime Minister faces a political headache over calls to act because her fragile administration depends on the support of the 10 Democratic Unionist Party MPs – who strongly oppose any reform to Northern Ireland’s strict laws.

Cabinet minister Penny Mordaunt – who is responsible for the women and equalities brief in Government – said the referendum signalled a “historic and great day for Ireland” and a “hopeful one for Northern Ireland”.

“That hope must be met,” she added.

Former women and equalities minister Nicky Morgan said the referendum result was “a huge milestone in the history of the Republic of Ireland and, I believe, the right decision”.

Mrs Morgan and three other former holders of the women and equalities role – Amber Rudd, Justine Greening and Maria Miller – all back Ms Mordaunt in support for reform in Northern Ireland, the Sunday Times reported.

But DUP MP Ian Paisley said Northern Ireland “should not be bullied into accepting abortion on demand”.

“The settled will of the people has been to afford protections to the unborn life and protect the life of the mother,” he said.

Commons Health Select Committee chairwoman and Tory MP Sarah Wollaston said: “I would vote to support an extension of abortion rights to all women across the whole UK.

“As this is a devolved issue, if an amendment is not accepted by the Speaker, then there should at very least be a referendum in N Ireland on this issue.”

Labour MP Stella Creasy claimed more than 140 parliamentarians had already signalled support for an effort to change the law in Northern Ireland.

And Liberal Democrat leader Sir Vince Cable said the Prime Minister should take advantage of the current lack of a devolved administration in Stormont and push for reform from Westminster.

Senior civil servants have been taking the majority of decisions within departments in Northern Ireland since the powersharing administration at Stormont collapsed 16 months ago.

Sir Vince told the Press Association: “The position in Northern Ireland is now highly anomalous and I think, probably, action will now have to be taken.”

Asked if Mrs May should intervene, he said: “Since there is, effectively, direct rule from Westminster, the Government has responsibility and it can and should take the opportunity to deal with this issue properly.”

Walthamstow MP Ms Creasy, who led a campaign to allow Northern Irish women to access NHS terminations for free in England, said “21st century abortion laws” should be extended across the British Isles.

In a message to the DUP she said the people of Northern Ireland “consistently support change” in the abortion law and it was “time to put them, not power in Westminster, first”.

The forthcoming Domestic Abuse Bill promised by ministers could be used as a vehicle for MPs hoping to change the law in Northern Ireland.

Abortions are currently only legal in Northern Ireland if the life or mental health of the mother is at risk.

While political leaders south of the border were at the forefront of efforts to liberalise the law during the referendum campaign, a majority of politicians in Northern Ireland do not favour the radical law changes now proposed in their neighbouring jurisdiction.

Shadow health secretary Jonathan Ashworth said he would back reform of Northern Ireland’s strict abortion laws in a free vote, but did not promise Labour would bring a bill before the Commons if the party was in charge.

Women should have the same rights as those elsewhere in the UK, he told Sky’s Ridge on Sunday, but stressed Labour must “tread sensitively and be aware of the realities of devolution”.