The ink is still drying on this morning’s deal between the Tories and the Democratic Unionists. The agreement is built on at least a billion pounds’ worth of extra funding for Northern Ireland.

The DUP has been in the national spotlight since the general election returned a hung parliament and the party became kingmakers.

The two partners in the deal have plenty in common: both are strongly in favour of retaining the Union and both support Brexit. But they still have their differences, particularly when it comes to abortion, gay marriage and climate change.

FactCheck investigates.

Climate change

Although not quite as green as they once were under David Cameron, the Tories say in their manifesto they want to “lead international action against climate change” and reiterate their commitment to the 2050 carbon reduction objective.

This is at odds with the DUP, whose manifesto didn’t mention the words “environment” or “climate change” at any point.

In 2008, the party appointed assembly member Sammy Wilson as its environment minister – a post he held until 2009, when he became finance minister for a further four years. Wilson is on record saying that he believes manmade climate change is a “con” and public discussion of it has become “fairly unformed hysteria”.

In 2013, Stormont representatives proposed a Northern Ireland-specific climate change bill, but in 2016, the DUP environment minister Michelle McIlveen told the Assembly that she didn’t think legislation was necessary.

More widely, the DUP has a patchy record on matters scientific. Seniors in the party, including current and former ministers in the Northern Ireland Executive, are members of the Caleb Foundation, an evangelical protestant group that believes the Earth is only a few thousand years old.

The DUP First Minister, Arlene Foster, tried to distance her party from the Caleb Foundation in 2016, saying “we have to see the Bible in the context of scientific developments”.

But that hasn’t reassured Greenpeace, who describe the party’s position on the environment as “worrying”.

Gay marriage

The Conservatives, in Coalition with the Lib Dems, brought in the first legislation to allow same sex couples to marry in 2013.

But under the DUP, Northern Ireland is the only part of the UK where same sex marriage has not been legalised.

Earlier this month, Marco Biagi, who was an SNP minister until 2016, said that Mrs Foster had written to him in 2015, asking the Scottish government to stop Northern Irish couples from converting their civil partnerships into marriages in Scotland.

Mrs Foster denied any recollection of such a letter. Mr Biagi responded by publishing it in full.

In it, Mrs Foster said that “neither of us would wish to place same-sex couples in an uncertain legal position”. But the certainty she wants to offer is probably not what many same-sex couples would welcome – if they are in a Northern Irish civil partnership, they cannot qualify to become legally married.

This isn’t the first time the party has been criticised for its stance on gay rights. Ian Paisley Jr, the son of the DUP’s founder Reverend Ian Paisley, once described homosexuality as “immoral, offensive and obnoxious”. He said later that he “[does] not hate gay people”.

Abortion rights

It’s 50 years since the Abortion Act was passed, allowing women in England, Scotland and Wales to terminate a pregnancy under certain conditions. It took effect in April 1968.

Abortions are still all but illegal in Northern Ireland, even if the fetus has a fatal abnormality, or was conceived through rape or incest. Only when there is a serious threat to maternal health can a doctor terminate a pregnancy.

In 2016, a 21-year-old Northern Irish woman was given a three month suspended sentence for breaking the abortion ban. She said she had bought pills online to abort the pregnancy because she didn’t have the money to travel to England for a formal medical procedure.

Taking pills to end a pregnancy without the consent of a doctor is illegal anywhere in Britain, but campaigners pointed out that the woman in this case would not have resorted to such measures if safe procedures had been available in Northern Ireland.

When she became First Minister last year, Arlene Foster said she would not extend the 1967 act to Northern Ireland because she “would not want abortion to be as freely available here as it is in England”.

But she did say she would “carefully consider” the high court ruling that said denying abortions to women who had been raped breached their human rights.

In 2012, some members of the Conservative cabinet – including Theresa May – expressed concerns about the 24-week limit on abortions. But neither the party nor the coalition government changed its official policy – nor did they suggest that terminations should be made illegal altogether.

What does this mean for Westminster politics?

It’s worth remembering that abortion rights and gay marriage are devolved matters – which is why the Northern Irish government has such a different stance to the rest of the UK in the first place. And much of climate change policy is for devolved administrations to decide.

And we should also bear in mind that today’s deal is not a formal coalition (like the one we saw between the Tories and Lib Dems) – it’s simply a commitment to back the government on “confidence” votes like the Budget and Queen’s Speech.

Both of these factors mean that the DUP will struggle to justify bringing their agenda on these issues to the Commons. And we’ve not seen any indication yet that they plan to.

Nevertheless, the DUP have rarely wielded as much power as they do today. We’ll have to wait and see how they use it.