Federal Ministry of Law in a rejoinder to National Accountability Bureau (NAB) has said that only Attorney General has been liable to write letter to the Swiss government over cases, sources said. Chairman NAB in a recently written letter to the ministry of law asked the ministry what steps can be taken for reopening of the Swiss cases against President Asif Zardari and whether NAB can directly contact the Swiss court or it has to use diplomatic channel through the government. The ministry of law in its letter said that the NAB can only file references and Swiss government does'nt recognize it.