Messi: What are the PSG fan tokens given to the footballer?

Lionel Messi holds his new Paris St-Germain jersey image sourceEPA

image captionPSG says it gave the star a 'large amount' of fan tokens

Football star Lionel Messi signed with Paris St-Germain (PSG) earlier this week after his shock exit from Barcelona.

As part of his welcome package to the club, he was handed "fan tokens".

The club says the tokens tie the Argentine star "with millions of Paris St-Germain fans around the world".

But what exactly are they?

The PSG fan token is a form of cryptocurrency, that allows people to be involved in decisions surrounding the club.

Using an app, they can help choose what message goes on the captain's armband, the design of the Paris St-Germain bus and the design of the curtain in the players' tunnel at the Parc des Princes stadium.

Fans can also choose the goal of the season and have their say in the club's end of season awards.

Some people have even received video calls from first team players via the app.

PSG says the app allows people to engage with the club in an innovative way.

Like Bitcoin and other digital currencies, fan tokens can be traded on exchanges. Just days before Messi officially signed for PSG, the club reported a high volume of trading of the token.

It said that trading volumes of the token exceeded $1.2 billion (£722m) in the days before his arrival. New sales generated about 30 million euros, according to Reuters news agency.

The value of the token rose over 130% in just five days amid reports Messi was heading to the Parisian club, Reuters reported.

It's not clear how many tokens the footballer was given as part of the deal but the club said in its statement that he had been given a "large number".

A number of clubs are following suit with Arsenal, Aston Villa and Inter Milan all announcing their own fan tokens.