STORY: Donald Trump has named former PayPal executive David Sacks as AI and crypto czar.

In a social media post, the president elect said Sacks would focus on making the U.S. a world leader in both fields.

He says his administration will ensure 'the crypto industry has the clarity it has been asking for'.

Trump once labelled such currencies a scam, but embraced the sector during his election campaign.

His victory has seen bitcoin surge on bets that the new administration will be friendlier to digital assets.

This week the top cryptocurrency broke through the $100,000 level for the first time, though it later dropped back.

It is up around 50% since Trump's election win.

Sacks was formerly chief operating officer at PayPal.

Among other things, he also founded the business social network Yammer.

He was an early advocate of cryptocurrencies, saying in a 2017 interview that bitcoin would revolutionise the internet.

One analyst told Reuters that Sacks was seen as a strong backer of crypto, with a history of investing in tokens besides just bitcoin.

Earlier in the week, Trump named strong crypto advocate Paul Atkins to run the Securities and Exchange Commission.

That added to optimism for the sector, with the U.S. financial watchdog hitherto seen as unfriendly to crypto.