Drugmaker Pfizer agreed to pay a $49 million (€49.8 million) settlement over allegations that it cheated the US government out of $20 million, according to the US Justice Department. Manufacturers selling drugs to the US government for distribution to the poor under the Medicaid programme are required by law to sell the drugs at the price offered to other favoured customers.

"The Medicaid programme was created to help ensure that those with lower incomes receive medical treatment - not to enrich drug companies or providers," said Mr Robert McCallum, assistant attorney general for the Justice Department's civil division.

Pharmaceuticals manufacturers are required to reimburse Medicaid for any difference in the price the government pays for a drug and the price it charges its favoured customers.