Nigeria's central bank has ordered the country's banking sector to report suspicious cash transactions from people involved in politics.

The move is part of sweeping reforms made by central bank governor Lamido Sanusi to try and stop corruption.

Mr Sanusi has sacked the heads of five top banks and has also brought fraud charges against several of their executives.

The regulations, published on the Central Bank of Nigeria website, now require banks to report large movements of cash between accounts if one of them belongs to a Politically Exposed Person.

These are defined as former heads of state, politicians, local government chairmen, court officials, soldiers and members of royal families.

The regulations are said to have become common elsewhere in the world since the September 11, 2001 terror attacks on the US.