One minister told The Independent the loss of her ministers did not in itself pose a terminal threat to May's government, but argued that the direction of travel had to change.
At least Mordaunt has served in two departments, Defence then Work and Pensions, and was a Minister of State, the rank just below cabinet status.
The quick Cabinet reshuffle had become necessary after 45-year-old Patel was forced to resign from her Cabinet post in charge of the Department for International Development (DfID) yesterday after days of controversy surrounding a series of unauthorised meetings she had held with Israeli officials, including Prime Minister Benjamin Netanyahu.
"While my actions were meant with the best intentions, my actions also fell below the standards of transparency and openness that I have promoted and advocated", Patel wrote in her resignation letter.
Patel's resignation was announced following a meeting with May on Wednesday at No. 10 Downing Street.
The reply ended a day of intense political drama as news channels tracked Patels flight back from Africa, where she had left for an official visit after her initial apology over undisclosed meetings while on holiday in Israel in August.More news: Suarez insists Barcelona know exactly what Coutinho will bring
It is the second mini-reshuffle in a week - after Ms Patel followed Sir Michael Fallon out of the Cabinet. "The existence of such a meeting would call into question the official account of Patel's behaviour and the goal of the visit". After Priti Patel was effectively sacked on Wednesday, senior Conservatives told The Independent the prime minister has until Christmas to improve the government's performance. She has been a strong cheerleader of the Modi government, publicly praising a number of its policies including demonetisation.
She used to work for former Tory leader William Hague, and was head of foreign press for George W Bush's presidential campaign in 2000. In March this year, she was awarded the Pravasi Bharitiya Samman award. As the United Kingdom looks to forge a new global identity outside the European Union in the years ahead the leadership of DFID, which saves and transforms the lives of the world's poorest people, has never been more important.
The MP for Guildford did not publicly disclose which side she supported during the European Union referendum.
Aside from her stance on Brexit, Mordaunt appears to share an eagerness to engage on India-related issues with Patel.
Mordaunt once famously delivered a speech on chickens purely so she could say the word "cock" in parliament.
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