In a statement, 64-year-old Bansal, who was made railway minister in October last year, claimed he has always observed the highest standards of probity in public life and nobody can influence his decisions.
He also sought an expeditious CBI inquiry into the issue.
"Regarding yesterday's incident involving my sister's firm in a CBI raid at Chandigarh, I have to say that I have no knowledge or proof about the matter at all. Though a close relative, he or any other relative of mine do not and cannot meddle in my official function or influence my decision. There is also no business relationship between his and my family. I have always observed highest standard of probity in public life and look forward to an expeditious investigation by CBI in the matter," he said in the statement.
Bansal's nephew V Singla was on Friday arrested by the CBI, which also held a member of the railway board in connection with alleged bribery of Rs 90 lakh for fixing a top level position in the government.
Singla was arrested in Chandigarh for allegedly accepting Rs 90 lakh in cash from Manjunath, the conduit of Mahesh Kumar, who was recently promoted as member, staff and who was trying to get a lucrative position as member, electrical.
Kumar was arrested in Mumbai by a CBI team soon after he had flown in from Delhi. CBI has registered a case under the Prevention of Corruption Act against him.
The other person arrested by the CBI was Sandip Goyal, who allegedly assisted in brokering the deal. Kumar was general manager, western railways and promoted recently as a member of the railway board, a post equivalent to that of a secretary in the government of India.
The railway minister has not yet ordered any departmental inquiry into the matter.
The railway board had recently appointed Subodh Jain as member, engineering, Mahesh Kumar as member, staff and Arunendra Kumar as member, mechanical. The post of member, traffic, is yet to be filled up.
The chairman of the railway board is retiring in June along with the finance commissioner and the entire railway board is expected to usher in new members.
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