LONDON (Reuters) - The chief executive of Dixons Carphone (>> Dixons Carphone) has quit Britain's largest electricals and mobile phone retailer to run the Boots chain in the country, Dixons said on Friday.

Sebastian James will step down after six years as CEO around the end of the company's 2017-18 financial year in April, Dixons said in a statement. He will be succeeded by Alex Baldock, who has been CEO of online retailer Shop Direct since 2012.

James will become senior vice president and president and managing director of Boots on Sept. 1, Walgreens Boots Alliance said in a statement.

The unexpected news came less than two weeks after Dixons' finance chief Humphrey Singer announced his resignation to take up the same role at clothing and food retailer Marks & Spencer (>> Marks & Spencer Group).

Dixons is scheduled to report Christmas sales data on Tuesday.

Boots in the UK is part of Walgreens Boots Alliance (>> Walgreens Boots Alliance), based in Deerfield, Illinois, which was formed in 2014 after Walgreens purchased the majority stake in UK and Switzerland-based Alliance Boots that it did not already own. It owns pharmacies, and wholesale and distribution companies.

Sky News first reported the news on Friday.

James first led Dixons Retail and merged it with Carphone Warehouse in 2014 to create Dixons Carphone.

"It is a much stronger company today than when he became CEO of Dixons Retail in 2012 with revenue, profit and customer satisfaction all substantially higher," said Dixons Carphone Chairman Ian Livingston.

However, James' strong track record was tarnished by a profit warning in August, which knocked 30 percent off the group's share price.

It blamed a weak mobile market as customers hold onto handsets for longer and in December Dixons reported a 60 percent slump in first half profit.

Shares in Dixons, down 46 percent over the last year, closed Friday at 195 pence, valuing the business at 2.2 billion pounds.

Shop Direct had said in October that Baldock would step down in 2018.

(Reporting by James Davey in London and Bhanu Pratap in Bengaluru; Editing by Adrian Croft and Richard Chang)