LONDON (Reuters) - Barclays ( JJCTF ) aims to hire up to 100 more advisers to drive growth in its private banking and wealth management business, but has ruled out a push into the United States because of heavy competition and high costs of entry.

Sasha Wiggins, chief executive of Barclays Private Bank and Wealth Management, said on Tuesday the lender had identified about 4 million Barclays UK customers with investable assets worth 250,000 pounds to 3 million pounds who could benefit from enhanced wealth management services.

"The UK is a large market with client investable assets totaling some 3.5 trillion pounds ($4.45 trillion), split across digital investing, affluent and private banking segments," Wiggins said in a presentation to analysts in London.

"It's a significant opportunity, both for the individual but also for the economy," she added, outlining plans to increase headcount and expand training of existing staffers.

Barclays ( JJCTF ) is one of several major international banks, including HSBC ( HSBC ) and Standard Chartered ( SCBFF ), looking to turbo-charge growth in their wealth management capabilities to offset declining revenues from lending in an environment of falling central bank base rates.

Besides the UK, Wiggins said Barclays ( JJCTF ) was chasing market share in Singapore, India and the Middle East, but the United States was "not a priority".

To complement the hiring spree, Wiggins said the bank would also increase its annual technology spending in the business by more than 75% from 2021-2022 levels, without giving details.

But she ruled out any acquisitions to accelerate growth. "I have every confidence I can deliver this plan organically," Wiggins said.

"This year alone, we've grown our net new assets under management by 3 billion pounds, around double the growth we saw for the equivalent period last year," Wiggins said, reiterating targets to deliver annual return on tangible equity in excess of 25% by 2026.

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