Former Archbishop of Canterbury Rowan Williams is joining African Anglican leaders as part of a Christian Aid campaign to highlight internally displaced refugees.

New research reveals the number of those forced to flee their homes who have remained in their country is more than double those who have fled abroad, raising questions about levels of support for states forced to rehouse millions of their own citizens.

The figures showed that last year alone, the equivalent of one person every second fled their homes and communities to find safety in other areas of their own countries.

The total was around 31.1 million and Lord Williams said they had been 'all but forgotten'.

He said: 'Media coverage, political interest and even the humanitarian community have been focused on those who are actually crossing borders or travelling to wealthier countries; but the vast majority of "internal refugees" receive almost no attention or support.'

He joined with Josiah Idowu-Fearon, the Anglican Communion's secretary general and former Archbishop of Kaduna, Nigeria, to urge world leaders to act.

'Violent attacks by terrorist groups like Boko Haram have caused people to flee, clinging to life in the most desperate situations,' he said.

'With so many people displaced, even proud nations like Nigeria look to the international community for help. The UN needs to address the plight of internally displaced people alongside the ongoing global refugee crisis.'

It comes after YouGov figures revealed a spike in interest in Christian Aid's refugee work with a TV advert judged to be a success.

The data company's Charity Index showed awareness among all respondent growing from +2 to +10 since mid-May.

The ad achieved particular prominence with those who would consider donating to the charity, with its Ad Awareness score jumping from +11 to +24 points over the same time frame.