Rail passengers have been warned to plan ahead for the Easter weekend due to major engineering work on some of Britain's busiest routes.

More than 400 projects are to be carried out as part of a £118 million investment by Network Rail, including work on the mainline between Norwich and London Liverpool Street.

A bus replacement service will be in operation on the line between Ingatestone and Newbury Park over the four-day weekend and passengers will have to use London Underground services to complete journeys in and out of the capital.

Network Rail says it schedules engineering work for bank holidays as there are fewer passengers than normal on those days.

The public sector company's chief executive, Mark Carne, said: 'This Easter, thousands of rail workers will be working round the clock to deliver crucial upgrades to the rail network as part of the £50 billion railway upgrade plan.

'This huge investment programme will provide faster, better services and help relieve overcrowding to respond to the huge growth on Britain's railways.

'While most of the network is open for business as usual, some routes are heavily affected and so we strongly advise passengers to plan ahead this Easter.'

London Euston - the UK's fifth busiest station - will be closed on Easter Sunday, with a reduced service on the previous and following day. There will also be disruption to services in and out of London Paddington.

Anthony Smith, chief executive of watchdog Transport Focus, added: 'For passengers wanting to travel over the Easter period, engineering works can be a major inconvenience, especially if it means having to use rail replacement bus services.

'Investment in maintenance and improvement is necessary, and passengers understand that.

'But our research is clear: passengers want to be kept on the train wherever possible, they want to know before buying a ticket if part of the journey will be by bus, and they want plenty of staff on hand to help.'

Analysis by Transport Focus in December last year found that passengers may have been 'misled' about whether their festive train trips would involve a replacement bus.

It discovered more than 2,600 omissions or errors in online journey planners.