Civil servants have been told to quit if they disagree with the Government's stance on Gaza, it has been revealed.
The Foreign Office's two most senior officials, Sir Oliver Robbins and Nick Dyer, responded to a letter by 300 staff raising concerns about Israel's conduct.
The staff letter, seen by the BBC, was sent to Foreign Secretary David Lammy last month and warned of 'complicity' in Israel's actions.
It also questioned continued British arms sales to the country and what they branded a 'stark… disregard for international law' by Israel.
In their response to the letter, Sir Oliver and Mr Dyer told staff their 'ultimate recourse is to resign' if they disagree with Government policy.
