By Richard Black
BBC environment correspondent
Britain's emissions of carbon dioxide, the main greenhouse gas, rose by 2.2% in the year 2002-2003, according to new government data just released.
Transport is a growing emissions sector
Environmental groups have accused ministers of failing to control greenhouse gas emissions.
Carbon dioxide emissions in 2003 were higher than when Labour came to power.
But the output of other greenhouse gases is falling, meaning that Britain is still on course to meet its Kyoto Protocol targets - just.
One reason behind the rise in emissions was the changing cost of basic fuels; the price of coal fell by 8% during the year, while gas rose by roughly the same amount.
But data also show that emissions from certain sectors - notably housing and transport - have been steadily rising for years.
"In overall terms, the figures are encouraging and put the UK ahead of most developed countries," said environment minister Elliot Morley in a statement.
"It is disappointing that there has been an increase in carbon dioxide emissions."
The various greenhouse gases vary widely in their "global warming potential" - the relative amount of warming produced by a given amount of the gas.
Comparing the volume of various gases would be meaningless; instead, scientists combine the volume with the global warming potential and express it in units called MtC - million tonnes of carbon equivalent.
Between 1997, when Labour came to power, and 2003, Britain's output of the three most important greenhouse gases has been:
Emissions of greenhouse gases in total are now 13.4% below 1990 levels, the baseline against which Kyoto Protocol targets are measured; Britain's target is 12.5%.
- Carbon dioxide - up from 153.9 to 156.1 MtC
- Methane - down from 16.6 to 11.1 MtC
- Nitrous Oxide - down from 16.6 to 11.0 MtC
But carbon dioxide emissions have fallen by only 5.6%. The government admits it will fail to meet a unilateral target, contained in Labour's manifesto for the 1997 election, of reducing CO2 by 20% from 1990 levels by the year 2010.
According to Friends of the Earth (FoE) UK, efforts to tackle climate change are "a disaster".
"Government failure to tackle climate change is even worse than feared," said the climate campaigner for FoE UK, Bryony Worthington.
"Unless the government takes control of UK emissions and starts delivering substantial year-on-year reductions, its 20% target will be impossible to reach."
The heart of the problem is that although CO2 emissions from industry have fallen - partly as a result of measures like the Climate Change Levy, a pollution tax - they are rising from other sectors.
Since 1990, residential emissions have risen by 11%, while the road transport contribution is up 8%.
The government is currently reviewing its climate change programme and is expected to announce new measures in the summer. These may include the introduction of renewable energy into the transport sector.