Method for validating an electronic transaction, and system thereof

A method for validating an electronic transaction, said method comprising:

• a step 100) of starting an electronic transaction by wirelessly transmitting identifying information from an electronic payment instrument module of a mobile phone to a point-of-sale terminal that forwards said identifying information together with transaction data to a retailer network and to a server;
• a step 110) of activating said mobile phone for starting a voice telephone call with the server;
• and
• a step 120) in which:
• the server replies to said voice telephone call and requests a customer utilizing the mobile phone to validate the electronic transaction by means of a validating PIN code;
• or
• a voice telephone call is initiated from the server to the mobile phone, wherein the server requests the customer to validate the electronic transaction by means of a validating PIN code;
• and
• a step 130) in which the customer validates the electronic transaction by entering the PIN code into the mobile phone, and the validating PIN code is communicated to the server during said voice telephone call.