Barclays Plc, the British bank that bought parts of Lehman Brothers Holdings Inc.’s American businesses, may cut as many as 5,000 jobs at the bankrupt company, Wall Street recruiters said.

The estimate, based on the $2.5 billion Barclays set aside for potential severance and retention costs, would mean half the Lehman employees transferred to the London-based company may be let go. Barclays, which agreed to pay $1.7 billion for the business, said it will decide in three months who will be offered permanent positions.

“They’ve paid for the right to choose through the ranks who they really want,” a partner at executive search firm Battalia Winston International in New York, Jo Bennett, said. “They’ll look at overlaps, decide whether they want to stay in all the businesses Lehman was in.”

Lehman, with more than 20,000 employees worldwide, filed for bankruptcy protection last week after it failed to find a buyer for the entire firm. Banks and brokerages have reduced their ranks by 120,000 since July 2007, when the subprime market crashed and sparked more than $522 billion in writedowns and credit losses.

Barclays won approval from American bankruptcy court last weekend for its purchase of Lehman’s American trading and investment-banking business. Barclays Capital, the securities arm, already had some 5,000 employees in the Americas region before the acquisition.