Last-minute talks are due to take place, but passengers are advised to avoid travel as services prepare to wind down.
Travellers are facing reduced train services across England, Scotland and Wales ahead of the biggest rail strike in 30 years.
A temporary timetable is due to be introduced later, but last minute talks between unions and rail bosses will continue this morning.
Disruption is expected across the week, with walkouts on almost all major lines on Tuesday, Thursday and Saturday.
Passengers should only travel by train if necessary, Network Rail says.
A strike will also take place across the London Underground on Tuesday, with Transport for London advising passengers to walk and cycle instead.
While two sets of talks are expected first thing this morning, the Rail Maritime and Transport Workers (RMT) union has said it will “intensify” its strike campaign if members don’t get an agreeable deal.
The union’s general secretary, Mick Lynch, said: “We will run this campaign for as long as it takes to get a settlement”.
He called on the government to “loosen the shackles” of employers to allow a deal to be struck, but Transport Secretary Grant Shapps said negotiations should be between unions and employers.
Network Rail says the last trains between many major cities are expected to depart over the course of the afternoon, before more than 40,000 rail workers walk out over job cuts, pay and conditions on Tuesday.
The reduced timetable will be in place until Sunday, with just 20% of usual services running on strike days.
Trains that do run will start later and finish much earlier than usual – between 07:30 and 18:30.
Knock on disruption is expected on the roads, with motorists being warned to expected a surge in traffic.
Motoring group the AA predicts motorway arteries, rural and suburban areas will be the worst affected, with drivers in Scotland and Wales expected to face long queues as most railway lines will be closed.
The M74, M8 and A9 in Scotland and the M4, A55, A5, and A483 in Wales could see severe traffic, it says.
The strikes will affect a number of events including school exams and the first Glastonbury festival for three years.
Rail strike advice
Can I get a refund? Yes, if you can’t get your train due to strike action. Season-ticket holders can apply for a refund for the days affected. Find more info here.
Do I have to go to work or school? This is up to your individual employer or school, check with them.
How can I plan my train journey? Use the National Rail journey planner.
The RMT is unhappy about stagnating pay and proposed job losses, and so far talks between the union and Network Rail – which maintains tracks and runs bigger stations – have failed to find a resolution.
Mr Shapps has dismissed a call from the RMT for ministerial intervention as a “stunt” – and claimed union bosses were “gunning for” industrial action.
Leaders at 13 trade unions and the Trade Unions Congress (TUC) have jointly written to Mr Shapps urging him to “help deliver a fair resolution”. The Labour Party has also called on the government to step in.
TUC general secretary Frances O’Grady said nobody takes strike action lightly but argued rail staff had been left with “no other option”.
“Many rail staff who will be hit hardest – such as caterers and cleaners – are on low and average earnings. It’s insulting to ask them to take yet another real-terms pay cut when rail companies took £500 million in profits during the pandemic,” she said.
However, Rail Delivery Group chair Steve Montgomery said rail bosses were trying to work with unions “on how to carry out modernisation and reform of the industry” amid falling passenger numbers.
“Ultimately we do want to give our people a pay increase… but we have to get on with reform, and that helps us deliver the next phase of giving people a pay rise.”
Rail strike basics
- When? There will be rail strikes on Tuesday, Thursday and Saturday and a London Underground Strike on Tuesday
- Where? Many lines will face disruption including: Avanti West Coast; C2C; Chiltern Railways; Cross Country Trains; Croydon Tramlink; Greater Anglia; LNER; East Midlands Railway; Elizabeth Line; Great Western Railway; Hull Trains; London Underground; Northern Trains; South Eastern Railway; South Western Railway; TransPennine Express; West Midlands Trains.
- Who? The RMT union’s members include everyone from guards and catering staff to signallers and track maintenance workers. Train driver members of the Aslef union will be striking on Thursday and 2 July on Greater Anglia and 28, 29 June and 13, 14 July on Croydon Tramlink.
How are the rail strikes affecting you? Are you having to make alternative travel arrangements? Will you miss an important event? Get in touch by emailing: email@example.com.
Please include a contact number if you are willing to speak to a BBC journalist. You can also get in touch in the following ways:
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