Visa invests in mobile payment start-up

Square benefits from strategic investment from Visa to aid its growth

Payment processing firm Visa has made a "strategic investment" of an undisclosed sum in mobile payments firm Square.

Square chief executive Keith Rabois said that Visa will take on the role of "strategic adviser" in the company's development, and this marks the beginning of a phase of aggressive international expansion.

Square provides businesses with a card reader that they can attach to their iPhone and Android smartphones, or iPad tablets, which allows merchants to process and manage credit card transactions on the go.

The firm was founded by Twitter co-founder Jack Dorsey, and it has just landed a lucrative deal selling its credit card readers in Apple's retail stores. Around $66m (£40m) worth of transactions have been made using the device since Square launched in October.

According to the LA Times, Visa's investment is in the "single-digit millions".