European countries where same-sex marriage is still illegal

Campaigners claim Northern Ireland is the only country "in western Europe" where same-sex couples can't get married.

But that very much depends on your definition of western Europe, although it is the last region of the UK not to have changed its laws yet.

On Saturday an estimated 10,000 demonstrators marched through Belfast demanding LGBT couples be treated "equally" under the law.

The largest political party in Northern Ireland, the Democratic Unionist Party (DUP), strongly opposes gay marriage.

Watch: Newsbeat investigates why Northern Ireland is the last place in the British Isles to allow same-sex marriage.

It goes against the religious beliefs of many of its supporters.

Because of the way the Northern Ireland Assembly was set up, the DUP also has the ability to block any legislation it doesn't like.

The others parties, including Sinn Fein, can also do this on issues it feels strongly about.

Civil partnerships are legal in Northern Ireland but many gay couples say they still feel like "second class citizens".

Those opposed to gay weddings deny Northern Ireland is "backward" and say most countries in the world have similar rules.

Newsbeat's Declan Harvey, who is from the Republic of Ireland where same-sex marriage was legalised last month, has been to see if the LGBT community in Belfast should be getting its hopes up.

There are three main challenges:

1. Northern Ireland is still a very Christian country, and many people say same-sex marriage is against Bible teachings.

2. The community is still split between those who support links with Britain and those who don't. This is the main issue that informs how they vote.

3. Parties within the Northern Ireland Assembly are forced to work together. This means they all have to agree before anything gets done. They don't agree on same-sex marriage.

However, LGBT organisations are planning legal action to challenge the ban on same-sex marriage in the courts.

No Gay Marriage Here: The Northern Ireland Story is part of the new Newsbeat documentary series

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