Tulloch has been employed by the insurance brand since 1992, progressing to a board-level position in June 2017, most recently as chief executive officer for international insurance.
Montague wrote: "Maurice knows our strengths, knows where we need to improve and has a deep understanding of insurance and customers' needs. He is exceptionally well qualified to re-energise Aviva and deliver long-term growth.”
Tulloch added: "I am honoured to lead Aviva, a business I've been part of for 26 years. There is a clear opportunity to realise Aviva's significant but untapped potential. Aviva is financially strong, we have a well-known brand and excellent businesses. But there is more to do to improve returns for shareholders."
Tulloch will receive a basic annual salary of £975,000 in 2019 and eligible for an annual bonus of up to 200% of salary, both pro-rated for the length of service as chief executive.
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