LONDON (Reuters) - Barclays pays women in its international division on average half of what men earn, the British bank said on Thursday, underscoring how major financial firms still have far fewer female employees in senior roles.

The mean gender pay gap in Barclays International, which houses the bank's investment banking unit, was 48 percent, Barclays said, meaning the average hourly wage for a woman was just under half that of a man.

Barclays joins a handful of major financial institutions that have disclosed gender pay gaps. The British government last year said it would require all companies with more than 250 employees to publish their gender pay data by April 2018.

British lawmaker Nikki Morgan, the chair of parliament's Treasury Committee, said the Barclays pay data was "shocking", adding that financial companies should be prepared to explain their pay gaps.

At Barclays, the difference was largely the result of the proportion of women working in more junior roles, rather than a breach of pay equality rules that require people working at the same rank to be paid the same regardless of gender, the bank said.

The bank reported a gender pay gap in its other main unit, Barclays UK, of 26 percent. Other organizations to have made such disclosures include U.S. investment banks like Citigroup, Wells Fargo and Bank of America, as well as the Bank of England.

Lloyds Banking Group said on Tuesday it would publish its pay gap before the April deadline.

(Reporting by Lawrence White and Emma Rumney; Additional reporting by Kirstin Ridley; Editing by Alexander Smith and Edmund Blair)

Stocks treated in this article : Citigroup, Bank of America, Wells Fargo, Lloyds Banking Group, Barclays