An all-party committee of MPs is investigating last month's London Stock Exchange computer crash.
They are to quiz stock exchange bosses and may call executives from Andersen Consulting which installed and manage the system.
The Commons Treasury Committee is deeply concerned by the failure of the stock exchange's IT systems on the last day of the tax year. The committee fears the crash will badly damage the City of London's reputation as a leading player in the international money market and wants evidence that steps are being taken to ensure against further failures.
So far the committee has scheduled a session when it will cross-examine London Stock Exchange chairman Sir John Kemp Welch, chief executive Gavin Casey, finance and operations director Jonathan Howell and business development director Martin Wheatley.
Former Tory minister Michael Fallon said the failure must never be allowed to recur. He is one of several committee members pressing for Andersen's representatives to explain what went wrong.
Labour MP Jim Cousins wants to know what happened to cause the trading platform to crash and was "very concerned'' about Andersen Consulting's role in the events. He echoed Fallon's concerns in warning that London's international position had been damaged by the fiasco and that there must never be a repeat of the circumstances which led to the crash.