Demonstrators hold placards as they take part in a protest by junior doctors, amid a dispute with the government over pay, outside of Saint Mary s Hospital, in Manchester, on March 15, 2023. AFP
With hundreds of thousands walking out, it was expected to be the biggest single day of industrial action since a wave of unrest began last year.
From nurses to lawyers, workers hit by a cost-of-living crisis have been striking across the economy, pitting unions against the government which insists big pay hikes are unaffordable and will only fuel inflation.
Alongside salaries, which workers say have not kept up with inflation, other issues include conditions, job security, and pensions.
Other groups walking out Wednesday included UK university staff and BBC journalists in England.
The strike by train staff in the Aslef and Rail, Maritime and Transport (RMT) unions in London left the Underground train network at a standstill.
Government departments and the Border Force were also hit by a walk-out of an estimated 130,000 members of the PCS civil servants' union.
PCS General Secretary Mark Serwotka said it was a scandal that some of those administering government services were now so poorly paid they were forced to rely on handouts themselves.
The spiraling strikes could no longer be ignored, he added.
"Doctors are on strike in our hospitals, train drivers are on strike. Teachers are on strike. I believe that for the first time in years, opinion polls show there's a lot of support for strikes," he told AFP.
'10 percent, Now!'
As Hunt delivered his budget plan to parliament, hundreds of striking civil servants marched near Prime Minister Rishi Sunak's Downing Street office chanting "What do we want? 10 percent, when do we want it? Now!"
Civil Service project manager Ben Millis, 25, said the country was witnessing an "amazing wave of activism".
"Prices of everything have increased so much, and it's the longest pay freeze... since pretty much pay records began," he told AFP as marchers blew whistles and banged drums.
"I think people are really starting to feel that something has to change and we need to get organized," he said.
The latest stoppage by teachers -- a two-day strike starting Wednesday -- was expected to affect every school in England.
Emmanuel Adebayo, 36, who teaches at an east London primary, said he had always dreamed of being a teacher.
But he said conditions were currently "deplorable" and often it was children with special needs and other vulnerable pupils who suffered as a result.
"I have considered leaving teaching but I love my job. That's why I'm here today, to make sure that things are better for other teachers to come," he said at a huge gathering of striking teachers in central London.
National Education Union leaders Mary Bousted and Kevin Courtney earlier threatened to step up their action if the government failed to put "money on the table".
"If they don't our action will escalate," they said in a joint statement.
"Shamefully, ministers don't seem interested in giving their own employees a fair pay rise to help them through the cost-of-living crisis and beyond."
UK hospital doctors in England on Monday launched a three-day stoppage claiming some were paid less than coffee shop workers.
The British Medical Association representing junior doctors says they have suffered the equivalent of a 26 percent cut to their pay since 2008-09.