Aegon will leave the Association of British Insurers at the end of the year, the insurer has announced.
Aegon plans to "put our point of view forward direct" to both the government and regulators, rather than relying on the ABI as its voice
Lobbying effectively was also understood to be among the reasons Legal & General left the ABI at the end of 2014.
Adrian Grace, CEO of Aegon, said: "Aegon has enjoyed benefitting from and contributing to ABI discussions over legislative, regulatory and industry-wide developments over the years.
"Looking ahead, we're entering an exciting new era with the Government encouraging innovation as it pursues its radical modernising agenda to meet the needs and preferences of consumers.
"The industry is responding positively, with each business developing its own priorities and strategies to meet their customers' needs.
"Aegon's strategy is to modernise our proposition, continue to build our multi-channel market leading platform, offer ‘to and through' retirement solutions and focus on advisers, workplace, protection, drawdown and guaranteed products.
"Integral to this is the emphasis on digital technology to enable us to better serve advisers, corporate clients and customers.
"With this in mind, we feel the time is right to separate from the ABI and focus on our strategic aims and put our point of view forward direct to the Government and regulators."
Responding to the news, Huw Evans, director general of the ABI, said: "It is always disappointing to lose a member, but given the changes within Aegon, this was not unexpected.
"The ABI remains the one voice of our industry which both Government and Regulators will engage with to progress their reforms and, with the Board's support, we continue to adapt our organisation to meet the changing needs of our membership as their business models evolve."
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