Scottish actor Ewan McGregor says more must be done to protect thousands of child refugees fleeing from conflicts in Iraq and Syria.

The Unicef ambassador was in Iraq last week to meet displaced families living in camps in the north of the country.

Tens of thousands of children are said to have been separated from their families because of the ongoing unrest in Iraq and neighbouring Syria.

Around 3.6 million children in Iraq are estimated to be at risk of being abducted and recruited into armed groups and face the constant threat of death, injury and sexual violence.

The actor, who has recently been filming Trainspotting 2, met families at the Debaga camp, near Makhmour, where more than 15,000 refugees are sheltered.

He also spent time with displaced Iraqi and Syrians living in camps in the nearby Erbil area.

During his excursion, he saw how those fleeing the IS-held city of Mosul have been provided supplies of water and food, as well as access to healthcare and child protection services by children's charity Unicef.

He said that "the world is facing an unprecedented refugee crisis" as he pressed for more to be done to address the issue.

The father-of-four said: "Children uprooted by conflict can find themselves alone, without family and in grave danger.

"No child should be alone. Many of the children I've met in Iraq have been forced to flee their homes, risking their lives on dangerous journeys and have been exposed to unimaginable horrors."

"One girl I met, called Myrna, told me how her family slept in a disused, half-constructed shopping mall for over a year," he added.

"The community donated food, clothes and supplies to her family and really came together to welcome displaced people."

The Scottish actor said that this act of humanity should be replicated everywhere, "especially on our own doorsteps".

He said: "It's up to us to tell our friends, our neighbours and our governments that refugees are welcome."

McGregor has been a Unicef Ambassador since 2004 and Peru, India, Nepal and the Congo are among the countries he has visited with the charity.