Billionaire entrepreneur Sir Richard Branson's appearance packs out Auckland's Vector Arena

Sir Ray Avery with Sir Richard Branson, who has packed out Auckland's Vector Arena tonight for an appearance in a "rare conversational format"

Billionaire entrepreneur Sir Richard Branson has packed out Auckland's Vector Arena tonight for a what's being billed as a talk about challenges and opportunities facing the world in a "rare conversational format."

Around 2000 guests have paid up to $999 to hear the Virgin Group founder speak at the black tie event.

According to Forbes, Branson is worth $7.12 billion.

Sir Richard told tonight's event entrepreneurs had to realise they would fail at times but none of the reversals he'd had were big enough to damage his group.

In response to questions from former prime minister John Key tonight at Vector Arena, he said Virgin Brides and Virgin Cola were among his failures.

He recalled having to dress up as a bride to launch the wedding company before it failed.

"I found out in Britain there were no virgin brides."

His cola company had been going well for a year until he was "kneecapped"" by Coke which flooded British stores with their products.

Key handled his new role as interviewer adroitly and got Branson to open up on:

What it takes to succeed?

"Taking an idea to make people's lives better. Just screw it and do it.

"The best businesses come from frustration or passion."

How to motivate people?

Branson said bosses running his businesses praised rather than criticised.

"You've got to water a plant to make it grow."

His space programme?

Branson said he hoped to get his first civilian astronauts 110km into space next year.

"We'll definitely be in space within a year."

Branson said 800 people had booked the $370,000 flights and he would be on the first flight.

The war on drugs

"You're pursuing something that is a failure."

He said Portugal's liberal approach to a heroin problem had worked.

Marijuana would be a mainstream medical drug within 10 years.

Climate change:

"It's sickening when you have the president of the free world not willing to listen to climate scientists."

He said governments needed to set ambitious goals.

Most interesting people he has met?

Nelson Mandela and Archbishop Desmond Tutu.

How chilled was Obama when he got to Neckar Island when he was replaced?

"He was remarkably chilled."

Branson said Obama was there to get away from the "horrors'" in the US.

Favourite food?

A good roast on a Sunday.

Coolest band signed up to Virgin Records?

The Rolling Stones.

Among the VIPs on tonight's guest list are fellow knights Sir Ray Avery, Sir Graham Henry, and Sir Peter Leitch; Dame Trelise Cooper, renowned chefs Michael Meredith and Ben Bayly; Olympians Blair Tuke and Peter Burling and Paralympian Liam Malone.

Newshub's Samantha Hayes is MCing the event and warned there was to be no recording or photography of the event.

Entree was salmon and avocado.

The dinner is raising money for Branson's Virgin Unite charity, with items ranging from beds, cruises to a Sealegs boat on offer. Drinks and dinner with Prime minister Bill English is on offer in the silent auction.

Former PM John Key, Dame Trelise Cooper and American Airlines country manager Mario Santander.

A dinner with Henry and Sir John Kirwan was also up for grabs, along with a signed copy of John Key's biography.

A round of golf with former Black Caps skipper Brendon McCullum went under the hammer for $6000.

Lunch for 10 people with rugby legends Sir Graham and Sir John at the French Cafe in Auckland sold for $11,000.

The bed went for $12,000.

The auction for drinks with Prime Minister Bill English and an overnight stay at the QT Hotel in Wellington for six people went for $22,000. Airfares were excluded.

Branson began selling mail-order records in the 1970s, a business which eventually became Virgin Records, before branching out to include air travel, a mobile phone network and finance.

He founded space travel company Virgin Galactic more than a decade ago with the aim of sending space tourists into low-earth orbit for $355,000 each.

His children Sam and Holly have been booked on flights. When he was here last in 2011 Branson met New Zealanders who had then signed up for the programme which has been hit by delays, although last year was licensed for space tourism.

The airline he founded, Virgin Atlantic, is working with a company that started in New Zealand to produce biofuel

LanzaTech last year announced it had produced nearly 5700 litres of low-carbon ethanol produced from waste gases for the airline, founded by Sir Richard Branson.

The company was founded in New Zealand 12 years ago and the parent company remains New Zealand-registered, while its headquarters have moved to Illinois.

Branson said then the breakthrough was a ''game changer" for aviation and could significantly reduce the industry's reliance on oil.

Dame Trelise Cooper with Sir Richard Branson.