Newly released drone video of a Rohingya refugee camp in Bangladesh has revealed the staggering scale of the humanitarian crisis, which has driven an estimated 515,000 people from their homes.

The video, filmed this month and released by the Disasters Emergency Committee (DEC), captures the sprawling Bulakhali camp – a carpet of makeshift tents and shacks blanketing the landscape for as far as the eye can see.

Some 515,000 Rohingya have arrived in Bangladesh from Myanmar's western state of Rakhine after Myanmar security forces responded to Rohingya militant attacks with a brutal crackdown on the ethnic minority group.

DEC said in a media statement that its member charities are on the ground responding to the call for aid, and that the UK government "will match pound for pound the first £3 (A$5) million donated by the public to the DEC Emergency Appeal".

The United Nations meanwhile is bracing for possible "further exodus", the UN humanitarian aid chief has confirmed yesterday.

UN under-secretary-general for humanitarian affairs Mark Lowcock reiterated the world body's appeal for access to the population in Rakhine, saying the current situation was "unacceptable" and that the crisis was one of the most "heart-rending".

An estimated 2000 Rohingya are escaping Rakhine daily for Bangladesh.