He joins as an executive director leading the firm's Global Solutions practice, working closely with Frank Lowenstein, another foreign affairs specialist who recently joined the firm in Washington DC. McGee will be based in London.
McGee took up his role as head of news at the Foreign and Commonwealth Office, as well as press secretary to the Foreign Secretary, in 2015, when the role was held by Philip Hammond, who is now the UK's Chancellor.
Johnson took up the role the following year, after his abortive bid to become Prime Minister in the wake of the Brexit referendum. Last year McGee accompanied the Foreign Secretary to last year's G7 in Italy and the United Nations in New York.
McGee also worked for the Department for International Development and the Department for Transport, and lead HM Diplomatic Service's worldwide media operation.
Prior to joining the civil service in 2011, he worked as a journalist for the Sunday Times and The Yorkshire Post.
APCO global CEO Brad Staples said: "Helping clients successfully navigate reputational challenges, investment opportunities, crises and complex geopolitical issues is at the core of what we do at APCO.
"Simon brings deep insights into the workings of government communications, extensive media relationships, a proven track record of building international communication networks and the valuable perspective of a former parliamentary lobby correspondent. We are delighted to welcome him to APCO and look forward to seeing the Global Solutions team grow further under his and Frank’s leadership."
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