Campaigners in Northern Ireland have welcomed the results of a new poll which shows public opinion for the change in law is overwhelmingly in its favour.

Activists have called for the UK government to introduce equal marriage legislation to bring the law for same-sex couples in line with that in England, Wales and Scotland.

The results of a recent poll show that 76% of Northern Ireland are in favour of marriage equality, with just 18% actively opposed, according to Sky Data.

These numbers – which is based on a representative sample of Northern Irish people – are the highest ever in support of same-sex marriages being legalised.

“We welcome this huge and ever-growing level of support for marriage equality in Northern Ireland,” said Patrick Corrigan of Amnesty International and a member of the Love Equality campaign for equal civil marriage.

“With 76% in favour and just 18% opposed to change, whatever else people in Northern Ireland may remain divided on, it is clearly not marriage equality.

“We are calling on the UK Government to recognise this huge public support for change. With no functioning devolution at Stormont, it is now time for the UK Government to legislate to bring Northern Ireland into line with the rest of the UK and Ireland and to end discrimination against the LGBT+ community.

Related: Defying the DUP to bring marriage equality to Northern Ireland

“Under the political surface, on human rights and equality issues such as equal marriage, Northern Ireland has changed. It is worth noting that this overwhelming support for marriage equality among the Northern Ireland public is far in excess of the figures which were seen in Great Britain or the Republic of Ireland in advance of changes in the law there.

“The Prime Minister has previously said that LGBT people in Northern Ireland should have equal marriage rights. This is now her chance to demonstrate action to match those words.”

Northern Ireland Assembly members have voted five times on whether Northern Ireland should legalise same-sex marriage so far, with the most recent vote in November 2015 being in favour of it being passed into law.

However, the Democratic Unionist Party (DUP) vetoed it using a petition of concern, a voting mechanism designed to protect the rights of minorities in Northern Ireland.

Same-sex marriage became legal in England and Wales in March 2014, and shortly followed in Scotland in December 2014.

Last month, a group of LGBTQ teenagers delivered a petition of more than 14,000 signatures to the Secretary of State’s office calling for the UK government to deliver marriage equality legislation at Westminster.

More recently, however, Conservative peer Baron Hayward proposed legislation to legalise same-sex marriage in Northern Ireland in a private members’ bill, which passed its first parliamentary stage in the House of Lords.