PayPal has started allowing U.S. customers to use bitcoin and the like at checkout.

People who hold cryptocurrencies in PayPal digital wallets will be able to convert them to regular money to make purchases.

Besides bitcoin, the system also covers ether, bitcoin cash and litecoin.

The service will be available at all its 29 million merchants in the coming months.

President and CEO Dan Schulman said it was the first time that cryptocurrencies could be used just as easily as a credit or debit card.

PayPal already allowed customers to buy, sell and hold virtual money.

Now the new move comes after bitcoin nearly doubled in value since the start of the year.

It's been boosted by signs that mainstream firms are betting on its wider adoption.

PayPal's launch comes less than a week after Tesla said it would take bitcoin as payment for its cars.

Schulman says the currency is now at a tipping point where it will become regularly used for transactions.