Rail bosses have assured Norfolk MPs that measures are being taken to prevent work on the line between Norwich and London from over-running and causing chaos for commuters.

A delegation of MPs demanded talks with Network Rail after passengers faced lengthy delays on two occasions last month because weekend engineering work had not been completed by the Monday morning.

That meeting was held at Portcullis House in London this week, with Norwich South MP Simon Wright, North Norfolk MP Norman Lamb and South Norfolk MP Richard Bacon meeting Network Rail route director Andrew Munden.

Liberal Democrat MP Mr Wright said: 'We were particularly keen to probe the problems in early November when there were delays of more than 70 minutes for some travellers because of engineering work which had over-run.

'We wanted to establish what was being done to ensure the problems were not repeated and were told there had been a concerted effort to improve co-ordination between Network Rail and National Express East Anglia.

'They told us there had been quality control issues in monitoring of contractors they had been using for the engineering work and they accepted that needs to be improved.

'We need to ensure in the next two years, before the award of the new franchise, that passengers from Norwich to London get the best possible service as it is immensely frustrating for both casual and business passengers.'

A Network Rail spokesman said: 'The meeting provided a welcome opportunity to speak to MPs from across the region and to reassure them that we take passengers' concerns extremely seriously.

'In partnership with National Express East Anglia we are introducing a number of changes to the way we manage improvement work, including better planning and stricter monitoring of work being delivered by contractors.

'We expect these changes to bear fruit immediately. At the same time we will continue to work with National Express East Anglia to ensure that once incidents are resolved, trains are able to resume a full service as quickly as possible.'

He added that, despite November's problems, punctuality of National Express East Anglia services had risen each year for the past four years.

However, rail passengers travelling between Norwich and London are still set for further disruption. This Saturday and Sunday no National Express East Anglia trains will run between Liverpool Street and Stratford because of engineering work. Passengers are urged to use the Tube at Stratford to get in and out of London.

Further work on Sunday will mean passengers will have to change trains at Colchester to get to Stratford.

And more disruption is due over Christmas because of a project to modernise and replace overhead lines on the main line in east London. This will mean using replacement buses on part of the route.

There will be no National Express East Anglia services on Christmas Day and Boxing Day and no trains between Ilford and London Liverpool Street between December 27 and 28 and January 1 to 3.

People will be able to travel on the Norwich to London route on the working days of December 29, 30 and 31, but on a reduced level of morning and evening peak hour services.