The Prime Minister has been accused of "sabotaging" deals to end strikes over the role of guards which are breaking out across the industry.
The Rail, Maritime and Transport union has written to Theresa May calling for her to allow train companies in England to negotiate in the same way as in Wales and Scotland, where it said settlements have been achieved.
The call came ahead of a fresh wave of 24-hour RMT strikes at Southern, Merseyrail, Arriva Rail North and Greater Anglia on Tuesday and Thursday.
The RMT said pickets will be out in force, taking the message to the public that axing of guards is part of a "co-ordinated strategy" driven by the Government.
RMT general secretary Mick Cash said rail companies were frustrated at being used as "political pawns", saying in his letter: "I am now becoming increasingly alarmed that you are sabotaging deals with the RMT.
"A number of train operating companies are privately indicating to me that that it is the Government that are preventing the deals that in normal circumstances they would be able to make with the RMT."
Greater Anglia is planning to run a full service on the strike days and Southern said there will be a normal service on most of its routes.
Arriva Rail North aims to run around 1,200 services across the North, 46% of its normal timetable, on both days between 7am and 7pm.
Most Merseyrail services will run between 7am and 7pm, with a break during the middle of the day, and some stations will be closed.
Southern's passenger services director Angie Doll said: "The RMT is striking about changes we made almost a year ago as part of our modernisation programme.
"Nobody has lost their job over this, in fact we employ more on-board staff to help passengers than we did before, and we are providing a better service with fewer cancelled trains."
Rail minister Paul Maynard said: "The RMT should stop using passengers as pawns in their political game, call off this strike action and return to talks.
"This dispute is not about jobs as all the companies have guaranteed posts and I have been clear I want to see more people working on the railways, not fewer.
"It's not about safety either as the independent regulator has ruled that driver-controlled trains are safe."
Paul Plummer, chief executive of the Rail Delivery Group, said: "Train operators are doing all they can to keep vital services running because jobs, businesses and passengers deserve and need a long-term investment and improvement plan, not short-term opportunistic strikes by the RMT leadership intent on dragging the country backwards."
RMT members on South Western Railway are also voting on whether to strike over the role of guards.