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Brexit and the UK's hung parliament should not hold up crucial projects such as the expansion of Heathrow airport, the government's top infrastructure adviser has said.

There must be a limit to the "dither and delay", said Lord Adonis, head of the National Infrastructure Commission.

He told the BBC that Brexit meant the UK had to be "open for business".

The government approved a third runway at Heathrow last October, but it was not mentioned in the Queen's Speech.

The National Infrastructure Commission is an independent body that provides the government with impartial, expert advice on major long-term infrastructure challenges.

It was set up by former Chancellor George Osborne in 2015 to oversee £100bn of spending on national projects.

Lord Adonis, a former transport secretary, has the backing of business groups including the CBI in his effort to press ministers for action.

He told the BBC's Today programme: "At the moment, Heathrow is running at capacity. We cannot be open for business if you can't get in and out of the country.

"It's 14 years since the original decision in principle was taken to proceed with Heathrow.

"There really is a limit to the dither and delay that we can engage in as a country when it comes to these massively important national infrastructure projects."

Lord Adonis also called for the government to press ahead with plans for a new £18bn nuclear power station at Hinkley Point in Somerset, despite last week's report from the National Audit Office calling it "a risky and expensive project".

He rejected suggestions that the government should rethink the project, saying: "All that 'think again' would do is put in jeopardy a large proportion of our electricity generating capacity for the future."