Ms Rudd telephoned Theresa May to tell her of the decision amid intensifying opposition demands for her to quit.
Here is Amber Rudd’s resignation letter in full:
Dear Prime Minister,
It is with great regret that I am resigning as Home Secretary. I feel it is necessary to do so because I inadvertently misled the Home Affairs Select Committee over targets for removal of illegal immigrants during their questions on Windrush.
Since appearing before the Select Committee, I have reviewed the advice was given on this issue and become aware of information provided to my office which makes mention of targets. I should have been aware of this, and I take full responsibility for the fact that I was not.
The Windrush scandal has rightly shone a light on an important issue for our country. As so often, the instincts of the British people are right. They want people who have a right to live here to be treated fairly and humanely, which has sometimes not been the case. But they also want the Government to remove those who don’t have the right to be here. I had hoped in coming months to devise a policy that would allow the Government to meet both these vital objectives - including bringing forward urgent legislation to ensure the rights of the Windrush generation are protected. The task force is working well, the residence cards are being issued well within the two weeks promised, and the design of the compensation scheme is making good progress.
The Home Office is one of the great offices of state and its job is to keep people safe. It comes with the responsibility to fight terrorism, support and challenge the police and protect people against abuse, as well as manage migration.
It has been a great privilege to serve as your Home Secretary. I have seen first-hand the second to none commitment and bravery of our police, fire and intelligence services, they truly are the best in the world and we should rightly be extremely proud of them.
I have been particularly pleased that we were able to set up the first Global Internet Forum for Counter Terrorism which has led the way with encouraging social media sites to go further and faster in taking down radicalising and terrorist material, which plays such a dangerous part in increasing extremism.
Setting out new laws to tackle the scourge of knife crime and acid attacks and helping to steer our young people away from a life of crime and violence by providing them with credible alternatives have been particularly important to me.
Opportunities to work on issues that safeguard the vulnerable, champion women and make a lasting impact on people’s lives particularly stand out for me. New policies to fight domestic violence and abuse against women are out to consultation, and will lead this country to taking a new approach. Helping to bring over thousands of refugees, including child refugees from both Calais and the Middle East region, and meeting some of the families who fled the terrible situation in Syria and have now been given a chance to rebuild their lives here in the UK in safety and security is something we can be proud of.
It has been an honour to work on a new security treaty with the EU as part of our new partnership going forward and to participate in your Brexit sub-committee helping to ensure that we have the best possible EU deal for our economy, businesses, jobs and people across the UK.
The new Economic Crime Centre that I launched with the first use of unexplained wealth orders will be important to the confidence of London as a financial centre.
I will continue to support the Home Office ministerial team whenever possible on all these important subjects, supporting the Government from the back benches and continuing to work hard for my constituents of Hastings and Rye.