"Dear Jeremy, It is with a heavy heart that I am writing to you to resign from the Shadow Cabinet. The result of the referendum last week means that our country is facing unprecedented challenges.
"Those who will be hit hardest by the economic shock associated with the vote to leave the EU need a strong opposition, as do those communities who fear rising levels of intolerance, hatred and division.
"More than ever, our country needs an effective opposition which can hold the Government to account and which is capable of developing a credible and inspiring alternative to an increasingly right-wing and backward looking Conservative Party.
"As much as I respect you as a man of principle, I do not believe you have the capacity to shape the answers our country is demanding and I believe that if we are to form the next Government, a change of leadership is essential.
"I would like to thank you for the opportunity to serve in the Shadow Cabinet. Yours sincerely, Heidi Alexander MP."