Insurer RSA's head of UK and Western Europe quits

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LONDON, April 16 (Reuters) - The head of British insurer RSA's UK and Western Europe business has resigned ahead of a strategic shakeup, the group's second top-level management change in two days.

RSA on Wednesday said Adrian Brown, who has worked at the group for 25 years, has resigned from the board but will stay in his executive role until a successor is appointed.

The announcement came a day after the group promoted its head of emerging markets to the newly created role of chief operating officer with a remit to oversee sales of non-core businesses as the group bolsters its balance sheet.

RSA is in the middle of a group-wide turnaround after a troubled 2013 marked by accounting irregularities at one of its divisions and high levels of claims driven by extreme weather in key markets.

The company's difficulties culminated in several profit warnings in 2013 and the departure of a number of senior figures, including chief executive Simon Lee who was replaced this year by former Royal Bank of Scotland (LSE: RBS.L - news) boss Stephen Hester.

"We have an ambitious business plan which now needs to be driven over a time horizon that Adrian could not reasonably commit to," Hester said on Wednesday.

Brown will take up a new role as Executive Chairman of Underwriting and Distribution at AJ Gallagher, RSA said.

(Reporting by Chris Vellacott; Editing by Erica Billingham)