UPDATE 1-Aviva says Snowball to quit, reshuffles top execs

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LONDON, April 23 (Reuters) - Aviva (AV.L: Quote, Profile, Research, Stock Buzz), Britain's biggest insurer, said on Monday Patrick Snowball, the head of its UK business, is to quit the firm at the end of June.

Snowball, who joined Norwich Union in 1989 but was beaten to the top job at Aviva by Moss, will become deputy chairman of Towergate Partnership, a fast-growing UK non-life insurer.

Aviva's announcement of Snowball's departure confirms an earlier Reuters story that he was leaving, citing a source familiar with the situation.

In a wider reshuffle of top posts by incoming group Chief Executive Andrew Moss, Aviva said Simon Machell, currently chief executive of Norwich Union General Insurance, will become head of its Asia Pacific business.

Tom Godlasky, chief executive of Aviva USA, will become the head of its North American arm, in charge of both its U.S and Canadian business.

Igal Mayer, currently CEO of Aviva Canada, will take Machell's job at Norwich Union, the firm said.

The changes, which will take effect when Moss takes the top job on July 12, came about because Moss wanted to change his executive team to reflect Aviva's wider geographic spread, with a bigger North American presence following last summer's acquisition of AmerUS, and a growing Asian business, the source said in the earlier Reuters story.