Four-time Olympic gold medallist Sir Ben Ainslie has revealed that he and his team are close to taking their America's Cup testing boat to water for the first time.

The Ben Ainslie Racing Team are expected to take part in preparation races in Portsmouth over the next two years ahead of the 2017 showdown.

"We're very well developed with our testing boat that we'll be sailing in the very near future," Sky Sports News quotes Ainslie as saying. "That's quite a milestone for the design and boat building team.

"We have been racing in a number of different types of competition this year, which culminates in the extreme sailing series final event in December in Sydney.

"With the base which is in full build, we expect to be operational by next May. So the team is doing really well, we have achieved a huge amount in the last eight to 10 months."

The Ben Ainslie Trust was launched in Portsmouth on Monday and welcomed the Duchess of Cambridge Kate Middleton as its royal patron.