EDINBURGH - Celebrities joined, and entertained, thousands of fundraisers for the homeless sleeping rough in a Scottish park in frigid conditions overnight Saturday, in what organisers described as the biggest event of its kind globally.

Around 8,000 people gathered in Princes Street Gardens in central Edinburgh to hear the likes of singer-songwriters Liam Gallagher and Amy MacDonald, and bands Deacon Blue and Frightened Rabbit, "busk" for the cause.

Live Aid founder Bob Geldof, Monty Python comic John Cleese, Olympian Chris Hoy, comedian Rob Brydon and Scottish First Minister Nicola Sturgeon were also among the well-known faces helping to keep participants fed and entertained through the night.

Geldof, who recalled sleeping rough in London when he first arrived in the city decades ago, hailed the turnout "magnificent" and said it was more than just a gesture.

"They're also sleeping out in disgust at something so criminal in one of the richest countries in the world," he told AFP.

The event was organised by charity Social Bite, which has become a magnet for celebrity support in recent years.

Actors George Clooney and Leonardo Di Caprio have visited their Scottish restaurants, which are staffed in large part by people who have struggled with homelessness.

Geldof called it "a cafe where you get your dignity back".

Josh Littlejohn, co-founder of Social Bite, said: "We've been really fortunate to get some high profile visitors.

"That really put the spotlight on our organisation, and really gave us a platform to do things like this, to really push things as far as we can, to make an impact and raise awareness about homelessness.

"Everybody attending has raised money - some of them lots and lots of money - so hopefully the event will raise between £3-4 million (3.4-4.6 million euros, $4-5.4 million) for homelessness, as well as putting it at the top of the political agenda."

A study commissioned by Social Bite to accompany the event found that child poverty is the main driver of homelessness in Scotland.

"We knew, anecdotally from meeting lots of homeless people, that almost anyone you meet who is homeless have been dealt some really terrible cards in life and suffered really harrowing circumstances," added Littlejohn.

"When you learn that it is typically as a result not of individual decision making but of the structures of society and the cards that people were dealt, it really compels you to be much more compassionate to those individuals and restructure society so that they are not so marginalised."

A series of reports in recent weeks have exposed the scale of inequality in Britain.

A social mobility commission created by the British government found a massive gulf between the life chances of people living in London and the rest of the country.

A few days after the publication of their latest report, the commissioners resigned en-masse complaining the government in Westminster is too focused on Brexit to deal with the issue adequately.

The Joseph Rowntree Foundation (JRF) recently revealed the first sustained increases in child and pensioner poverty for 20 years in England, where homelessness rose by almost 50 per cent between 2009/10 and 2016/17.

However, homelessness dropped by nearly a third in Scotland - which is run by a semi-autonomous nationalist government - and it now has the lowest levels of poverty in Britain, according to the JRF.