Network Rail is due to publish a report on Monday following its inquiry into the late running engineering works that led to chaotic scenes at King’s Cross, Finsbury Park and Paddington stations this Christmas.

King’s Cross station had to close all day on Saturday, December 27 while nearby Finsbury Park station became so crowded that it, too, had to close for a time.

Paddington station should have opened at 7am on December 27 but was shut until 1.14pm after engineering work at nearby Old Oak Common overran.

The overruns put under the spotlight the salary levels and performance-related bonuses of National Rail top bosses, with transport secretary Patrick McLoughlin describing the problems on December 27 as “totally unacceptable”.

Later, National Rail chief executive Mark Carne announced that he would not be taking his 2014/15 annual bonus which could have been as high as £135,000.

The National Rail internal inquiry has been led by the company’s infrastructure projects managing director, Dr Francis Paonessa.

The work near King’s Cross was at Holloway in Islington and was being carried out by team from National Rail and engineering company Amey.

It involved work on track and points renewal and should have been completed in time for the start of operations to and from King’s Cross on the morning of December 27.

It was not until the following day that King’s Cross was able to open.

The work at Old Oak Common, in north west London, was a signalling contract carried out by contractors Signalling Solutions Ltd.

The physical work on this contract was completed in the early hours of December 27 but paperwork hold-ups meant a delay in being able to open Paddington.

The Office of Rail Regulation (ORR) is also holding an inquiry into the overruns.

ORR chief executive Richard Price will give evidence on the overruns to the House of Commons Transport Committee next Wednesday.

Also appearing before the committee will be Mr Carne and National Rail’s network operations managing director Robin Gisby.