The chief executives of V/Line, Public Transport Victoria and Metro Trains are due to appear before a public hearing on Tuesday about disruptions to V/Line's services.

The hearing is part of a parliamentary inquiry into Victorian infrastructure projects.

Ms Allan has been invited to appear at the inquiry by the chair of the Economy and Infrastructure Committee, Liberal MP Josh Morris.

The Opposition has accused the government of "passing the buck" over V/Line's problems.

Regional rail commuters face at least another four months of pain as operators try to fix a wheel wear issue that has forced numerous regional trains out of service.

An interim timetable beginning on Monday will be in place for Bendigo, Ballarat, Geelong and Gippsland services for five weeks.

Buses replacing trains will continue to be free, but those travelling by train will be charged as usual.

V/Line's acting chief Gary Liddle has also been forced to defend links between V/Line chairwoman Jenny Dawson and a bus company contracted to provide replacement services, which is owned by her husband.

Mr Liddle on Friday insisted the board and senior V/Line management had "no involvement whatsoever" in selecting bus companies to provide services.