Dhaka , Bangladesh ( CNN ) -- Nobel Laureate and microfinance pioneer Muhammad Yunus faced a new government fight Monday as the Cabinet ordered `` legal action '' against him for what it called `` tax irregularities . '' The Cabinet meeting , led by Prime Minister Sheikh Hasina , discussed a report prepared by the National Board of Revenue that claimed it had found tax irregularities by Yunus between 2004 and 2011 , said cabinet secretary Mohammad Musharraf Hossain Bhuiyan at a briefing . The allegations are related to his overseas earnings of about $ 6.4 million , including award money and royalties from his books , and possible improper tax exemptions . Yunus , who won the Nobel Peace Prize in 2006 , however , denied the allegations in a news release issued by Yunus Center in Dhaka . It said the government was supposed to determine what earnings were taxable . `` Professor Yunus has done everything with the consent and approval of the governing body , '' it said . `` Professor Yunus had brought all his overseas earnings through banking channels as per laws and showed them in his income tax return and paid all the applicable taxes . '' The National Board of Revenue chairman , Ghulam Hussain , said on Monday the board would seek an explanation from Yunus and take legal action if the explanation was found to be unsatisfactory . On Tuesday , the U.S. State Department urged the Bangladeshi government to treat Yunus `` in a fair and transparent manner , in keeping with Bangladeshi law and the principles of due process . '' This is not the first time that Yunus and the government have been at odds . In 2011 , Bangladesh 's central bank removed Yunus as managing director of Grameen Bank , citing a mandatory retirement age . Yunus , 73 , founded Grameen Bank three decades ago to reduce poverty in Bangladesh . The model of financing the extremely poor without requiring any collateral was replicated around the world . Yunus was also awarded the U.S. Presidential Medal of Freedom in 2009 and a U.S. Congressional Gold Medal in April .
The Bangladeshi government accuses Sheikh Hasina of tax irregularities . Improper tax exemptions on about $ 6.4 million among the allegations . U.S. , who won ` Professor Yunus in 2011 , says he paid all taxes as required . The government forced Yunus to retire from his Bangladeshi in 2011 .