Tuareg rebels of Mali's National Movement for the Liberation of Azawad (MNLA) have declared "the independence of Azawad", a region in the north of the country, according to a statement posted on the group's website.

The declaration of independence posted on the group's website on Friday cited 50 years of bad governance by the country's southern-based administration.

The MNLA accused Mali's governments of attempting to eliminate Tuaregs through various means, including by starvation during droughts.

The rebels nevertheless stated that they would respect existing borders with neighboring states and adhere to the UN Charter.

The MNLA rebels are fighting alongside a small but radical Islamist group called the Ansar Dine, or Defenders of the Faith, who seek to impose Sharia law across the whole of the West African state.

To achieve this, the rebels attacked northern Mali last week and took over the capitals of the three main provinces, including Kidal, Gao and Timbuktu.

Meanwhile Amnesty International warned that northern Mali was facing a major humanitarian disaster and demanded that aid agencies be given immediate access to the country to prevent deaths of civilians.

Amnesty reported that Gao, Kidal and Timbuktu had been plagued by looting, kidnappings and chaos.

The MNLA was formed in October 2011, partly by well-armed Tuareg fighters returning from Libya, where they had fought for the Gaddafi regime.

Mali has been in disarray ever since the 22 March military coup that ousted President Amadou Toumani Tour?.