Theresa Mays team has been hit by the departure of a second key aide in a matter of days after her official spokeswoman announced she would leave on Friday.
Lizzie Louden said she was leaving government to move on to other things as Ms Mays election campaign had barely started.
It follows the departure of Katie Perrior, who along with Ms Louden, was brought in the wake of Ms Mays leadership campaign win last year.
The pairs exit leaves Ms Mays election campaign firmly in the hands of Fiona Hill and Nick Timothy, the two trusted aides that Ms May has relied on going back to her days in the Home office.
But it also comes amid claims that Ms May relied on too tight a circle of advisors, refusing to allow others into her circle of trust.
Ms Louden joined the May camp after working on the Leave campaign and before that had worked as an advisor for Iain Duncan Smith and a government press officer at the Department for work and Pensions.
Announcing her departure, Ms Louden said: I always thought and intended that my departure from Government last year to work on the Leave campaign would be final and I would move on to other things.
None of us expected a leadership campaign, but I was honoured to work on Theresas campaign, and to come into Government.
Ms Perrior resigned earlier this week saying she had never intended to stay on past an election.
She had taken an extended leave of absence from her role as co-director of PR agency iNHouse Communications to work on Theresa Mays leadership campaign before she took up the Downing Street job.
Ms Hill and Mr Timothy have worked for Ms May for years, notably as part of her inner circle at the Home Office implementing her policy ideas and communications.
Scottish-born Ms Hill, a former Sky News editor, is known as a sharp operator with wide-reaching control over the No 10 operation.
She was sacked as a special adviser in 2014 for releasing a confidential letter during the dispute with Michael Gove over alleged extremism in schools, but was reappointed by Ms May as soon as she became Prime Minister.
Mr Timothy helped Ms Mays Tory leadership campaign and is said to have been instrumental in her key policy ideas including the push for grammar schools.
He is from a working-class background and attended a grammar school. As former director of the New Schools Network he also drove the free school agenda.