Perrior, who is also formerly head of press at ITV and later Channel 4 News, is taking extended leave from iNHouse Communications, where she is a co-director, to work on the Home Secretary’s campaign.
Perrior's agency – jointly led by another ex-Conservative staffer Jo Tanner – ran Boris Johnson’s PR during his 2008 bid to become London Mayor, and his successful 2012 re-election campaign.
She also worked with May earlier in her career at Conservative HQ.
Perrior’s appointment comes as the five contenders firm up their teams for the upcoming Conservative Party leadership election. Guido Fawkes reported yesterday that Lord Tim Bell, Margaret Thatcher’s former press chief and chairman of Bell Pottinger, is advising Andrea Leadsom in her campaign, which had its official launch on Monday.
At #AndreaLeadsom4Leader launch I spy Lord Bell, former Thatcher advisor, "Are you advising Leadsom?" "Yes."— Guido Fawkes (@GuidoFawkes) July 4, 2016
As PRWeek reported last week, May is also being advised by Fiona Hill of Lexington Communications, alongside Stephen Parkinson, formerly of the Vote Leave campaign, and May’s former chief of staff Nick Timothy.
Paul Stephenson, latterly the PR head of Vote Leave, has joined the team steering Michael Gove's campaign.
Voting in the first round of the leadership election takes place today among the 330 Conservative MPs, with further rounds expected until only two candidates remain. The winner will be named on 9 September.
Yesterday Johnson, who had already ruled out his own leadership bid, endorsed Leadsom for the role. Support for the energy minister among Conservative MPs has grown sharply, with some reports putting her level with or ahead of Gove, with May retaining the most support.