* Archie Kane, Helen Weir to leave
* CEO Antonio Horta-Osorio to take charge of insurance unit
* Shares down 0.3 percent, in line with broader market (Adds comment, details on departing execs, updates shares)
By Myles Neligan
LONDON, March 9 (Reuters) - Lloyds Banking Group said its insurance and retail bosses were stepping down, taking analysts by surprise with the speed, if not the nature, of new chief executive Antonio Horta-Osorio's boardroom cull.
Retail director Helen Weir has decided to leave and insurance director Archie Kane will retire, Britain's biggest retail bank said on Wednesday.
The departures came after Horta-Osorio, formerly head of Spanish bank Santander's British arm, took over as chief executive of the bailed-out British lender on March 1.
"It is the new chief executive stamping his authority on the reporting lines," said Simon Willis, banks analyst at stockbroker Daniel Stewart & Co.
Exane BNP Paribas analysts noted the only remaining board members from the team of previous CEO Eric Daniels would be finance director Tim Tookey and wholesale boss Truett Tate.
"We speculated that at least half the executive board would go during 2011. With Daniels, Weir and Kane gone, that is three out of five within less than two months of the new CEO's formal arrival, somewhat quicker than expected, albeit otherwise unsurprising," they said in a note to clients entitled "The Axeman Cometh".
Weir, a former manager at consultancy McKinsey & Co, arrived from retailer Kingfisher in 2004 as finance director before taking over the retail division in April 2008, months before Britain's banks were plunged into crisis. At the time the move was seen as a step on the way to the top job.
Kane joined the board in 2000 before taking over insurance operations in 2003. He has worked at the group since 1986.
The bank's insurance division, which includes leading life and pensions group Scottish Widows, will report directly to Horta-Osorio in future.
There has long been speculation Lloyds may sell insurance assets as it seeks to bolster its balance sheet. Analysts have said a lack of ready buyers makes major disposals unlikely.
Lloyds could clarify its intentions on asset sales at the end of June when it unveils the results of a strategic review launched by Horta-Osorio.
Lloyds is 41 percent owned by the British government after being bailed out during the credit crisis when it was saddled with billions of pounds of losses after the takeover of troubled rival HBOS in 2008.
Its shares were down 0.3 percent by 1000 GMT, with the blue-chip FTSE 100 share index also 0.3 percent lower and a European banking sector index down 0.4 percent. (Additional reporting by Paul Hoskins; Editing by Greg Mahlich and Dan Lalor)