Commuters travelling to work on Monday will face new measures on trains and at stations, amid worries more people might use public transport to return to work in England this week amid the easing of coronavirus lockdown restrictions.
Currently, only those who cannot work from home should travel to their workplace, the government has said.
In the rest of the UK, the advice from the devolved administrations is to avoid all but essential travel.
From Monday, around 70% of the standard rail timetable will be running, up from 50%.
But in a bid to enable social distancing, their capacity will be reduced to as little as 10% of normal levels, and passengers are being urged to avoid non-essential travel.
What are the current lockdown restrictions in England?
Seats may be removed or blocked off to try and ensure social distancing is observed.
British Transport Police will have more officers at London stations in a bid to control crowds.
Passengers could be prevented from boarding trains or entering stations and platforms if they are deemed to be too full.
Social distancing guidelines recommends remaining at least two metres away from others in bid to help prevent the spread of coronavirus.
It is also possible that if a train becomes relatively busy early on in its route, then it may not stop at later stations.
Passengers travelling by train are being asked to wear a face covering.
Many rail operators say passengers will only be able to board trains with a reservation and many stations will have a one-way system in place.
So, what are different rail operators doing?
East Midlands Railway
Will Rogers, managing director at EMR, warned that the new timetable “will only allow a small rise in the number of passengers we can accommodate”.
He added: “We urge everyone to only go by train if it is necessary and keep public transport for key workers and those who must travel.”
London North Eastern Railway
Passengers using LNER are only allowed to board trains if they hold a reservation as well as a ticket.
The operator is asking passengers to sit in a window seat, with one person per row of four seats, and two empty rows between each passenger.
People travelling as a household will be allowed to sit together but must maintain “a safe distance” from other passengers.
Avanti West Coast
Avanti West Coast warned its customers that anyone without a reservation may not be able to travel on their choice of train due to capacities being limited to around a quarter of normal levels.
Train operator Northern said there will be “significantly reduced capacity on each and every one of our trains”.
Nick Thomas-Symonds, Labour's shadow home secretary, said there is "clearly" an issue that public transport can "become too crowded".
He said without access to a car, much of the country must rely on public transport to get to work and there needs to be a "safe environment in terms of getting to work".
"The government needs to take these things into account and to plan on that basis when the top priority should be safety on public transport so people can actually commute to work in a safe environment".
Labour had been calling for a plan to made for public transport over-crowding contingencies for weeks.
Meanwhile the Rail, Maritime and Transport union described the increase in train services as a “high-risk strategy” and expressed concern that “rushed political considerations could well override the safety issues for staff and passengers”.
It has called for new compulsory protections for passengers and rail workers, including the enforcement of two-metre social distancing on trains and the compulsory wearing of face masks by passengers, which should be provided for free at stations and be able to be disposed of safely.
RMT general secretary Mick Cash said: “We are opposed to the early relaxation of lockdown measures and believe that non-essential workers should avoid using trains.
"When people absolutely must use a train, there should be new compulsory protections.
“We have the crazy situation of Eurostar passengers arriving with masks on into St Pancras but then not wearing masks when they transfer to the tube or other rail services.”
A Department for Transport spokesperson said the message remained that people should only go to work if they cannot work from home and they should avoid public transport if possible and maintain social distancing if they have no other choice.
They added: “We have asked operators to increase the number of services from today to help reduce pressure on the transport network, providing more space for social distancing as well as delivering increased reliability and extra capacity for the future.”
The resumption of more train services comes at the start of the first full working week since Boris Johnson set out his plan for easing the coronavirus lockdown in England, urging those employees unable to work from home to return to their places of employment.
He has faced criticism from some unions and opposition MPs who accused him of moving too quickly while the devolved administrations in Scotland, Wales and Northern Ireland have refused to follow suit.
Recycling centres in England will reopen after a reported increase in fly-tipping, discount chain Poundland will reopen 36 stores, and early-morning swimmers can enter the water at Britain’s oldest swimming club at the Serpentine in Hyde Park, west London.
And The Times newspaper reported lorry drivers will make up the bulk of exemptions to plans to impose a 14-day quarantine on international travellers regardless of mode of travel.
The paper said hauliers will account for around two-thirds of those who will not be asked to self-isolate in what it called a “blow to the airline and tourism industries”.
Further exemptions are to be agreed at a Cabinet meeting, the Times added.
A further £84 million has been invested in teams from Oxford University and Imperial College London as they carry out clinical trials in a bid to find a vaccine that could finally end the pandemic.
Oxford has signed a global licensing agreement with pharmaceutical giant AstraZeneca which could see it supply 100 million doses of a vaccine – with 30 million going to the UK – if the current human trials prove successful, Business Secretary Alok Sharma said on Sunday at the Downing Street news conference.
Despite the announcement, the prime minister earlier warned there was still a lot to do and the search may never be successful.
The latest Department of Health figures showed 34,636 people had died in hospitals, care homes and the wider community after testing positive for coronavirus in the UK as of 5pm on Saturday, up by 170 from the day before.
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