Scottish Secretary David Mundell has said he wants the Democratic Unionist Party (DUP) to "change its position" on LGBTI issues.
Prime Minister Theresa May is due to meet DUP leader Arlene Foster on Tuesday to finalise a deal on propping up her minority government.
Mr Mundell, Conservative MP for Dumfriesshire, Clydesdale and Tweeddale, was reappointed Scottish Secretary in a post-election Cabinet reshuffle on Sunday.
He became the first openly-gay Conservative Cabinet secretary when he came out in January 2015.
Questioned on the DUP's stance on gay rights, he said he does "not subscribe" to the Northern Irish party's position.
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Northern Ireland is the only part of the British Isles where same-sex marriage remains outlawed.
The DUP has repeatedly used a controversial Stormont voting mechanism - the petition of concern - to prevent the legalisation of same-sex marriage despite a majority of MLAs supporting the move at the last vote.
Mr Mundell told BBC Radio Scotland's Good Morning Scotland programme: "I don't subscribe to the DUP's position on these issues but the DUP will not be influencing these decisions within the rest of the United Kingdom.
"We're not in any way signing up to the DUP manifesto. Most of these issues are devolved to the Northern Ireland Assembly."
He added: "I would like to see the DUP change its position, and indeed Northern Ireland as a whole change its position, on LGBTI issues.
"Ruth Davidson has been very clear on that, she actually went out to Northern Ireland and set that out, so they can't be in any doubt where they stand on these issues.
"I think change is brought about, certainly in Northern Ireland, by persuasion, by people working together and the best way actually to achieve these is to get the Northern Ireland Assembly back up and running, and I hope that will also be possible."