HUNDREDS of picket lines have mounted outside government offices, schools, hospitals, universities and stations on Wednesday, as the biggest walkout for years threatens to overshadow the Budget.
In Scotland, more than 130,000 members of the Public and Commercial Services (PCS) union are on strike, with thousands taking part in a rally in Edinburgh.
The disputes are over pay, jobs, pensions, conditions and cuts, with warnings of more strikes if they are not resolved.
The strike has scaled back the business of the Scottish Parliament and closed the public gallery as well as around 1000 picket lines organised at job centres, DWP offices, Historic Environment Scotland and, for the first time, HMRC.
Across the UK, up to half a million junior doctors, teachers, civil servants, lecturers, London Underground drivers, BBC journalists and Amazon workers are taking industrial action.
Some of the strikes, such as those by teachers, will only be held in England as progress has been made in Wales and Scotland.
A third teachers’ union in Scotland has voted to accept an improved pay offer – with Holyrood’s Education Secretary Shirley-Anne Somerville saying the move means the threat of further strikes in schools was lifted.
However, more than 70,000 staff members of the University and College Union (UCU) will begin the first of three successive days of strike action.
Speaking ahead of the rally, PCS Scotland industrial officer Joy Dunn said: “PCS members serve the public in Government departments across the four nations of the UK.
“They play important roles in delivering essential public services and are unwilling to put up with any further erosion of their pay at a time when the workload is increasing and travel, energy and food costs are all increasing.
“This cannot go on; our members need a pay rise and to be treated fairly by employers."
In London at 1pm, after walking from the Tube station at Embankment, the demonstrators stopped on Whitehall outside Downing Street for a rally.
They chanted: “What do we want? 10%”, “when do we want it? Now” while many blew whistles, as the Chancellor was delivering his speech in the nearby House of Commons.
Union leaders will address a rally in Trafalgar Square and strongly criticise the Government over its handling of the public sector disputes.
BBC journalists walked out just after 11am on Wednesday from the radio and main entrances at Broadcasting House in central London.
Around 25 journalists left the building to join officials from the National Union of Journalists (NUJ).
At Holyrood, Green MSPs will not cross virtual or physical picket lines as staff from the PCS union go on strike, the party has confirmed, and a rally was held on The Mound in Edinburgh.
Some strikes, such as those by teachers, will only be held in England as progress has been made in Wales and Scotland.