Climate change should be tackled in "as cheap a possible way", George Osborne said on Thursday as he called on environmentalists to drop their "ideological" opposition to nuclear power and shale gas.

In some of his most significant remarks on climate change since he said in 2011 that Britain should go no faster than any other EU country in cutting carbon emissions, the chancellor said it was important not to be "theological" about finding the right energy mix.

In a question and answer after a speech to business leaders in Hong Kong, the chancellor firmly rejected arguments posed by some Tory climate change sceptics when he said man is to blame for global warming. The chancellor said: "I'm someone who believes climate change is happening, that it's caused by human beings. We should do what we can to prevent it and if we can't prevent then mitigate against it for example by building flood defences."

But Osborne then added that climate change should be tackled in an inexpensive way. He said: "Where I would differ from some is I would say: 'Let's try and do this in as cheap a possible way as we can'.

"Let's not be too theological about which technology we use – let's get the right mix. For example, there are people in the green movement who oppose civil nuclear power for I would think rather ideological reasons but it's clearly a low-carbon source of energy generation.

"Equally shale gas has done incredible things to reduce US carbon emissions and there are parts of the environmental movement who don't like that, again for rather ideological reasons. I would say let's see more fracking and shale gas in Europe, in the UK and in China."

Osborne has tried to encourage the exploitation of British shale gas reserves by offering tax breaks. In his speech, he said: "Far from shying away from difficult issues like nuclear energy and fracking – my government is leading the way in Europe."

The remarks by the chancellor about tackling climate change in an inexpensive way chime with the message delivered to modernising Tories when a minister, who is a close Osborne ally, said last year that the prime minister wants to get rid of the "green crap". The chancellor told the modernisers that he accepts the need to tackle climate change but does not want to harm economic growth in the process.