UK Uncut, the anti-cuts campaign group, has celebrated the success of its first worldwide weekend of protests, and promised more international days of action to come.

The group – which is less than six months old – co-ordinated demonstrations from London to Hawaii. Its Big Society Bail-In is designed to highlight the range of services it says will have had to be cut in order to support the financial sector.

In Britain, there were protests in over 40 banks. Parents and children transformed branches of RBS, NatWest and Lloyds into creches, classrooms and drama clubs. Teenagers turned branches into youth centres. Protesters also set up laundries and libraries, homeless shelters, walk-in clinics and job centres.

In America there were more than 50 demonstrations under the umbrella of US Uncut, which is just three weeks old. Over 100 protesters temporarily closed a Washington DC branch of the Bank of America, which received and repaid $45bn in the 2009 US federal bailout. US Uncut said the bank exploited the tax code to pay no federal income taxes in 2009, while paying its top executives millions of dollars.

Daniel Garvin, a spokesman for UK Uncut, said: "The day went extremely well. The actions have hammered home the link between the crisis caused by the banks and the cuts to our essential services. The movement has gone international.

"It's become a global issue, proving people can work across borders to tackle issues like corporate tax avoidance and cuts to services."

The group's previous target was Barclays, which recently admitted it paid just £113m tax in the UK in 2009 on reported profits of £11.6bn.

This weekend's target was the 84% state-owned RBS, which paid more than 100 of its bankers over £1m last year. Total bonuses at the bailed-out bank reached almost £1bn, despite reported losses of £1.1bn for 2010.

Other banks' branches, including NatWest and Lloyds, in which the Treasury holds 41% of shares, were also targeted.

Activist Ruth Griffiths said: "RBS, NatWest and Lloyds would have all collapsed if it were not for the billions given to them by the taxpayer. It was their greed and reckless gambling that caused the economic crisis, yet while ordinary people are paying the price in cuts to vital services and benefits, like hospitals, creches and disability living allowance, they are awarding themselves obscene bonuses."

Fellow protestor Aisha Atkins said: "There are alternatives to the cuts, for example, making the banks pay for a crisis they created or by stopping tax dodging by big business and the super-rich. But the government is making a political choice to reduce the deficit by making ordinary people pay with job losses and savaged services. RBS's bonus pool alone could pay for around 45,000 nurses."

Tim Jones, a UK Uncut co-founder, said the banks' "tax avoidance, reckless banking, and unjust cuts" have become "international problems that need international action by ordinary people".

"This international day of action will be one of many to make governments around the world stand up to the banks and make them pay for their crisis, and to ensure the super-rich stop dodging tax," he pledged.