Lloyds Banking Group's
Lloyds said on Monday that Tookey would remain with the company until the end of February next year, and added that it had already begun looking for his successor.
Friends Life, which is a division of British insurance vehicle Resolution
Tookey's departure follows that of former Lloyds retail banking head Helen Weir and insurance head Archie Kane, following Horta-Osorio's arrival at the helm.
Canaccord Genuity analyst Cormac Leech said Horta-Osorio could promote his former colleague at Santander UK
Lloyds had poached Bostock from rival Royal Bank of Scotland
Tookey's departure may have been merely ahead of Osorio lining up a new candidate for the role, Leech wrote in a research note.
Tookey already has experience of working in the insurance industry, having been a finance director at British insurer Prudential
Tim's extensive FTSE leadership experience makes him an excellent addition to the team. He will play an important role in building a profitable new business franchise and preparing the business to position it strongly for the full range of potential Resolution exit options, Friends Life's chief executive Andy Briggs said in a statement.
Resolution was set up a few years ago by entrepreneur Clive Cowdery to acquire and restructure struggling life insurance companies, and in August it said that its half-year profit had more than doubled to 390 million pounds ($616 million).
The British government has a stake of roughly 41 percent in Lloyds and holds 83 percent of rival Royal Bank of Scotland after it had to bail out both banks with taxpayers' money during the credit crisis.
European competition regulators have ordered both banks to sell off assets to compensate for their state bail-outs, and Lloyds is currently in the process of looking to sell some 630 retail bank branches.
($1=0.633 British Pounds)
(Editing by Greg Mahlich)