John Suffolk, the government's chief information officer, is to step down at the end of the year in what could be a major setback to Downing Street's efforts to overhaul public sector IT projects.
Ian Watmore, chief operating officer of the Efficiency and Reform Group, will become chairman of the CIO Council until further notice, the Cabinet Office confirmed.
"It has been a great honour to have been a civil servant and a huge privilege to have led the IT profession over the last five years. Without doubt we have transformed the UK into a leading user of technology, benefiting citizens and the UK economy," said Suffolk in a statement.
"I am immensely proud of the way we have supported the new government in its first six months, and have greatly enjoyed working with [Minister for the Cabinet Office and Paymaster General] Francis Maude and his team.
"I know that with his drive and passion for delivery the very good work we have started will continue and be a great success."
Suffolk's decision to step down comes just five months after he was given additional powers to reduce expenditure by overhauling ICT infrastructure in Whitehall.
He also headed up a team to oversee government IT and launch critical projects including the G-Cloud and a government apps store, both of which now face an uncertain future.
Suffolk joined the Home Office in 2004 as director general, leading the technology transformation of the Criminal Justice System. He was appointed government chief information officer in 2006.
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