Nasa and SpaceX’s historic launch has been aborted due to bad weather conditions, just minutes before take off.

An estimated 1.7 million people from around the world tuned in to watch take-off from The Kennedy Space Centre in Florida on Wednesday.

But bad weather prevented what would have been the first launch of Nasa astronauts from US soil in nine years, with the capsule now due to attempt lift-off on Saturday.

The launch was aborted with 17 minutes to go before lift off.

The Falcon 9 rocket was set to lift off at about 9.30pm (UK time) with the Crew Dragon capsule carrying Robert Behnken and Douglas Hurley to the International Space Station.

The US Air Force's 45th Weather Squadron, which monitors the weather for air and space operations, had forecast between a 40 per cent and 60 per cent chance of favourable conditions at the launch site in Florida.

Nasa, which has strict rules about the conditions for manned crew missions, said of one these rules was being violated just minutes before the launch.

In a clip tweeted by Nasa, mission control could be heard telling the two astronauts the launch was being postponed.

After being told “unfortunately, we are not going to launch today”, one of the crew replied: “It was a good effort by the teams and we understand.”

The earliest the SpaceX Falcon 9 rocket and the Crew Dragon spacecraft could depart is this weekend, with potential launch windows available on Saturday and Sunday.

Among those to respond to the mission being postponed was British astronaut Tim Peake.

He wrote on Twitter: “What a shame – @SpaceX launch is scrubbed, but the rules are there in the interest of safety. A great rehearsal and reset for the next launch attempt in 3 days, Sat 30th at 15:22 (ET).”

Ivanka Trump, who was at the space centre for the launch, told of her disappointment as take off was scrubbed with just 17 minutes to go.

"The launch of the SpaceX Crew Dragon to the ISS was scrubbed 17 minutes before the scheduled launch due to inclement weather," she wrote on Twitter.

"Leaving Kennedy Space Centre now ... disappointing, but safety first! Launch will be rescheduled!"

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