Hundreds of scientists rallied outside Britain's finance ministry on Saturday against planned government cuts they say will harm the country's international reputation as a research hub. Britain's Conservative-Liberal Democrat coalition government is due on October 20 to announce harsh measures to tackle a record deficit of 154.7 billion pounds (188 billion euros, 242 billion dollars). Demonstrators at the Treasury in central London chanted 'Hey Osborne! Leave our geeks alone' to the tune of the Pink Floyd song 'The Wall', calling on finance minister George Osborne to ringfence science budgets. 'They really are thinking of dismantling UK science. It makes absolutely no sense,' said biologist Jenny Robin, the founder of the Science is Vital campaign which organised the protest. Imran Khan, director of the Campaign for Science and Engineering the UK, said he expected cuts of up to 30 percent in science investment. 'We could be on the verge of a catastrophic collapse in our science and engineering base,' Khan told the crowd, before leading a chant of 'Save British Science.' Opponents of the cuts say they will hurt the economic recovery and there have been signs in recent days that the government, which came to power in May, may scale back or at least stagger the measures. But Conservative Prime Minister David Cameron insisted at his party's annual conference on Wednesday there was 'no other responsible way' to firm up the economy. The government has also drawn fire for new immigration rules that 10 Nobel laureates warned earlier this week could prevent the world's best brains working in Britain. 