Colonel Richard Kemp has told Daybreak that there has been an increase in attacks to British troops in Afghanistan.
He said: "The Taliban know we are getting out in 2014 and their efforts are focused on showing the world and their supporters that they are driving us out."
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The former foreign minister said that Parliament should be willing to reject a deal that is not in the UK's best interests.
The country's top defence officer said the force may ignore any order to launch a nuclear attack which is deemed to be illegal.
Navy officials say they have received seven short satellite calls which are though to have come from the submarine.