Citigroup's female employees earn 29 percent less than their male counterparts, the Wall Street bank revealed on Wednesday, while announcing targets for appointing more women and minorities to senior roles.

The median pay for Citi's women employees globally was just 71 percent of the median for men, while that for minorities in the United States was 93 percent of the median for non-minorities, the company said, citing an internal analysis.

The third largest U.S. bank also said it would hire more women globally and black employees in the United States to senior roles.

By the end of 2021, it wants at least 40 percent of roles at assistant vice president level through to managing director level to be held by women, and 8 percent of such roles in the United States to be held by black employees.

Currently, more than half of Citi employees globally are women and over 45 percent of its U.S. workforce are minorities, the company said.

"We know we need a comprehensive approach to our diversity initiatives to make the progress we want to see," Sara Wechter, head of human resources at Citi, wrote in a blog post.

Citi, along with other Wall Street banks and financial companies, has been under pressure to disclose how much less it pays women than men.

A 15-year study by the Washington-based Institute for Women's Policy Research found last year that American women earn an average of 39 percent less than men but that this figure rises when taking account of time off for family or childcare.