Tesco has unveiled a £30m deal for a US firm to take on the management of its IT network.

New York-state based firm CA Technologies will oversee the infrastructure behind the supermarket giants growing online empire, including Tesco Bank, Tesco.com and Tesco Mobile.

Tesco Bank was hit by major computer glitches earlier this year and Mike McNamara, Tesco's chief information officer, said: "Our systems infrastructure needs to work for our IT team in order to do their job for our customers, our colleagues and our suppliers."

CA Technologies has 472,000 staff working in more than 5,000 stores across 14 countries.