The new £20 and £25 price plans for 30 days and 12 months give customers "unlimited" data for as much mobile internet browsing and Facebook searching as required - up to a fair usage policy of 500MB.

The 30 day SIM-only plans give customers 600 minutes anytime, unlimited texts and unlimited data for £20 or 900 minutes anytime, unlimited texts and unlimited data for £25.

The 12-month SIM-only plans offer 900 anytime minutes, unlimited texts and unlimited data for £20 and 1200 minutes anytime, unlimited texts, unlimited data and unlimited calls to landlines for just £25.