Carrie Gracie, the China editor for Britain's public broadcaster the BBC, has resigned from her post in Beijing due to pay disparities with her male colleagues, according to an open letter she wrote.

The BBC has come under fire recently for paying male employees more and has pledged to close the gender gap by 2020.

In July, it revealed as part of a funding settlement with the government that it paid its then top male star five times more than its best-paid female presenter, and that two-thirds of on-air employees earning at least 150,000 pounds ($203,500) were men.

In a letter published on her personal blog on Sunday, Gracie said there was a "crisis of trust" at the broadcaster, where she has worked for 30 years, and that it was "breaking equality law and resisting pressure for a fair and transparent pay structure".

The BBC had four international editors, two men and two women, of which she was one, she said.

When the BBC revealed top salaries as part of last year's settlement, Gracie said she learned that the two men made at least 50 percent more money than the women in those roles.

She said she had since had been offered a pay increase that remained "far short of equality" and left her post in Beijing last week, returning to her former job in the BBC TV newsroom.

"The BBC must admit the problem, apologise and set in place an equal, fair and transparent pay structure," she said, calling for an independent arbitration to settle individual cases at the broadcaster.

The BBC cited a BBC spokeswoman as saying that "fairness in pay" at the corporation is "vital", and that an audit of pay for rank and file staff led by an independent judge found there was "no systemic discrimination against women".