However, the company also reported a 59% gap on the mean measure for hourly pay for 2017.

HSBC has a median gap of 61% for bonus payments between its male and female employees.

The bank said it had fewer women in senior management roles, while many top global roles were based in the UK, where its group head office is based.

Elaine Arden, group head of human resources, said: "If we identify any pay differences between men and women in similar roles, which cannot be explained by reasons such as performance/behaviour rating or experience, we make appropriate adjustments."

The 29% figure is more than double the 14.2% reported by Barclays for its UK retail banking operations for 2017, but lower than Lloyds Banking Group (42.7%) and Royal Bank of Scotland (36.5%).

HSBC said its pay gap was largely down to the fact it - like its rivals - has fewer women in senior roles, with just 23% of higher positions held by women.

Across the whole organisation, however, it employs more women than men.

HSBC has a target to try to improve its gender balance and is aiming to have 30% of senior roles held by women by 2020.

All firms with more than 250 staff must report their gender pay gap to the government by 4 April.

The median figure refers to the midpoint of all workers' salaries from lowest to highest paid.

The mean describes the total wage bill divided by the number of employees, which means it can be skewed by a small number of very highly paid workers.