Just 43% now think a coalition government was the right decision for Britain, down from 59% in May

Support for Britain's first peacetime coalition in 70 years has fallen dramatically since David Cameron and Nick Clegg launched the government in the Downing Street rose garden last May, according to the latest Guardian/ICM poll.

The poll finds that after six months of Conservative-LibDem rule just 43% think coalition government was the right decision for Britain while 47% now disagree. In May, in answer to a slightly differently worded question, 59% backed the coalition while 32% disagreed with the decision to form it.

Rising Labour support has cut into the government's popularity. Other results from the poll, published earlier this month, put Labour support at a three-year high of 39%. Lib Dem support was at a five-year low of 13%. The Conservatives were on 37%, up one point from November.

There is a mixed picture for Clegg and Cameron among their party's supporters in the poll, which was carried out before Christmas. A slim majority of Lib Dem voters still support the coalition. Among people who voted Lib Dem last May – many of whom have now switched support – 46% think the coalition was a mistake, while 47% remain in favour.

David Cameron can take comfort from continued strong Tory backing for coalition rule: 76% think forming the coalition was the right thing to do. This will be welcomed by Downing Street which is under pressure from the Tory right over the coalition.

John Redwood, the former leadership contender, today expressed irritation with the way in which Lib Dems were allowed to take credit for the "nice" things done by the coalition. "One of the things I do not like is the 'new narrative' that Lib Dems have come into the government to bridle the instincts of Conservatives," he said. "This storyline entails allowing Lib Dems to claim credit for all the nice things that happen."

Redwood's criticism comes as this latest poll suggests that signs of economic recovery in 2010 have not persuaded voters that the worst is over. Ahead of next month's rise in VAT to 20% many people are preparing to cut spending. While almost half, 45%, say the change will make no difference, 38% claim they will spend less and a further 17% say more.

Many are pessimistic about the prospects for public services. Almost half of those questioned – 49% – say things will get worse for the NHS, while 12% say it will improve. There are also fears for the future of state education: 54% say 2011 will be a worse year for schools than 2010, while 10% think it will be better. There is little sign of public backing for the coalition's promised reforms to schools and health: even among definite Conservative supporters, only 13% say schools will improve in 2011 and 15% say the same of the NHS.

Asked about the party leaders, only 12% thought Nick Clegg's prospects would improve in 2011, against 47% who think he will have a worse year. For David Cameron, 23% think 2011 will be better and 36% worse. Only Ed Miliband can look forward to a happier new year. While 27% think the coming year will be worse for him than the one before, 29% think it will be better – the only net positive score on all the issues asked in the survey.

• ICM Research interviewed a random sample of 1,003 adults aged 18+ by telephone on 16-19th December 2010. Interviews were conducted across the country and the results have been weighted to the profile of all adults.