Priti Patel won’t “go quietly” to the back benches and will continue “fighting for a successful exit from the European Union”, according to sources close to the Witham MP.

Ms Patel was forced to resign last week after it was revealed she held secret meetings with Israeli officials – including prime minister Benjamin Netanyahu – when she was international development secretary.

The meetings were held during a private holiday in August and Number 10 and the foreign office were not told.

After days of pressure following the revelations Theresa May finally summoned Ms Patel back from an overseas trip to Kenya and Uganda. Ms Patel quit her post and admitted her action “fell below the high standard that are expected of a secretary of state”.

In her resignation letter she added: “While my actions were meant with the best of intentions, my actions also fell below the standards of transparency and openness that I have promoted and advocated.

“I offer a fulsome apology to you and to the Government for what has happened ... From the backbenches I will take an active role representing and speaking up for the good people of the Witham constituency. I look forward to highlighting the great entrepreneurial spirit in this part of Essex that has created new jobs and growth.”

But a Tory source has predicted Ms Patel will come back fighting: “She is too determined and has too much to offer the party and the country to just sit on the backbenches for very long. I am sure of that. She won’t go quietly and fade into the background.

“For a very long time she has wanted Britain to leave the EU and I believe she will now take a very keen interest in ensuring that is achieved in the best possible way not just for her constituency but for the whole country. She will be fighting for a successful exit from the EU.

“It was probably right that she went. But very sad. The cabinet is weaker without her – I know that is an opinion a lot of people share.

“I suppose it is good news for Witham although I know she continued to put every effort into her constituency even when she was a cabinet minister.

“When we have a new regime at the top of the party Priti will be in the frame again. And post-Brexit – with her positive outlook about Britain’s place in the world – I imagine she will be invaluable.”