By politics.co.uk staff
Protesters, union leaders and ministers are considering their next move after yesterday's public sector pensions strike.
The government has sought to play down the impact of yesterday's walkout, claiming 80% of civil servants were at work as usual and less than half of the Public and Commercial Services (PCS) union's members took strike action.
But union leaders claimed members had "voted with their feet" to support the strike.
PCS general secretary Mark Serwotka told a rally in Westminster: "We are in it together with public sector workers, students and pensioners defending everything we have fought for for generations.
"Three quarters of a million have been out today, there will be four million in October."
National Union of Teachers general secretary Christine Blower said the profession had offered a "fantastic response" to the strike action.
The walkout has not swayed ministers' resolve to raise pension contributions or increase the retirement age to 66 for all, however.
Cabinet Office minister Francis Maude said: "Very few civil servants wanted this strike at all – less than ten per cent of them voted for it - and they are right.
"It is simply wrong for their leader to be pushing for walkouts when serious talks, set up at the request of the TUC itself are still ongoing. As Brendan Barber himself said, the government are approaching this whole process in good faith."
The Metropolitan police said 40 people were arrested in the main march through central London from Lincoln's Inn Fields to Westminster.
Fifteen people were charged with offences relating to public order, obstruction and assault on police. Nine were arrested for breach of the peace but were subsequently released.