Welsh MP for Clwyd West David Jones is seeking a Commons debate after post masters raised questions over the Post Office's Horizon accounting system.
He told BBC Wales, "I am sure something is going on and the Post Office needs to answer the questions that these people are asking. I am going to ask for a debate at the House of Commons."
BBC Wales investigated the problem for the current affairs programme Taro Naw, broadcast on Tuesday on S4C.
The programme follows up on Computer Weekly's investigation into IT at the Post Office.
Computer Weekly spoke to post masters who had experienced problems with their accounts, finding deficits they could not explain. Some lost their life savings or became bankrupt paying back the deficits, and said they suspected their accounts system Horizon of producing the anomalies. The Post Office denied there were any problems, and said the system is robust and processes millions of transactions every day.