O2 has launched "simplicity", a new range of pay monthly tariffs that provide competitive calling rates and can be ended on 30 day's notice at any time.

The new Simplicity tariffs bridge the gap between long-term contracts and Pay As You Go.

This new plans are aimed to appeal to the one third of mobile phone users in Britain who opt to keep their existing handset when their contracts are up.

"For those people who are perfectly happy with their existing handsets, O2 simplicity offers great value for money and, with the ease of direct debit payment, a lot less hassle", Sally Cowdry, marketing head honco of O2, said.

O2 are also promoting the green aspects of the new plans pointing out the potential 7.5 kilograms of CO2 emissions that come with a new device.

In addition, for every online simplicity tariff taken with paperless bill O2 are donating £5 to the O2 Energy Saver Fund administered by the Energy Saver Trust.

O2 simplicity tariffs start from £15 a month for 200 minutes and 200 texts, simplicity SIM only tariffs are available from all O2 stores and via the link below.