The biggest strike day in over a decade begins today, ITV News Political Editor Robert Peston reports
Hundreds of thousands of workers walk out on strike today in separate disputes over pay, jobs and conditions.
The fresh wave of walkouts will culminate in what will be the biggest day of industrial action for more than a decade across the UK.
It will be the biggest day of action since 2011, when well over one million public sector workers staged a one-day strike in a dispute over pensions.
Teachers, train drivers, university lecturers, civil servants, bus drivers and security guards in seven trade unions will stop work on the same day.
Here, ITV News takes a look at the sectors affected by the strikes:
The Department for Education (DfE) has offered a 5% pay rise to most teachers for the current school year, but the NEU is demanding a fully funded above-inflation pay rise for teachers.
Support staff in Wales, who are members of the NEU, will also take part in the action.
Teacher members of the NEU in sixth form colleges in England, who have already been balloted and taken strike action in recent months, will join the walkouts in a separate but linked dispute.
Meanwhile, school leaders in the NAHT Cymru union will hold industrial action short of a strike - which includes abstaining from arranging cover for those taking part in any industrial action - from February 1.
On Wednesday, teacher members of the EIS union - Scotland’s biggest teaching union - will take action in Clackmannanshire and Aberdeen as part of an ongoing dispute over pay.
ITV News' Faye Barker breaks down the different strikes that will be taking place on Wednesday
Train driver members of Aslef and the Rail, Maritime and Transport union (RMT) will walk out on Wednesday in a long-running dispute over pay, jobs and conditions.
A second wave of national strike action is then slated to commence on Friday.
The walkouts will leave some areas with no trains at all and those that do run will start later and finish earlier than usual.
Some 14 rail operators will be affected by the strike action, including:
Avanti West Coast
East Midlands Railway
Great Western Railway
GTR Great Northern Thameslink
London North Eastern Railway
South Western Railway (depot drivers and SWR Island Line)
West Midlands Trains
Elsewhere, around 1,900 members of Unite employed as bus drivers by Abellio in London will head for picket lines.
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Around 70,000 staff at 150 universities will strike as part of action by the University and College Union (UCU).
The long-running dispute is over pay, working conditions and pensions.
The Universities and Colleges Employers Association (UCEA), representing 144 employers, said it has made a "full and final pay offer" of between 8% and 5%, which the union described as a marginal improvement.
Meanwhile, the employers said the offer prioritises the disproportionate effect of high inflation falling on the lower paid, with a minimum of 5% for all other members of staff.
Up to 100,000 members of the Public and Commercial Services union (PCS) will strike in another long-running dispute.
Those taking part work for government departments, the Border Force, museums and other government agencies.
The PCS is seeking a pay rise of 10% after the government paid 2%, which the union complained was well below the soaring rate of inflation.
Huge job losses and cuts to redundancy terms for those affected are also feared by the union.
Outsourced security guards at UCL, represented by the IWGB, will also be on strike, demanding a pay rate of £15 an hour, union recognition and an end to outsourcing of services.
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