The ECB has been forced to postpone the publication of its plan to improve diversity in English cricket, amid the abrupt departure on Thursday of one of the only two non-white chairs of a first-class county.

Mehmooda Duke, who was also the only female in such a high-profile county role, and one of only three female board members from black or minority ethnic backgrounds, had been due to step down at the end of March to take up a new role as High Sheriff for Leicestershire.

However, she has now chosen to depart with immediate effect, stating that "cricket had been torn apart by recent events", and calling for "fresh leadership at national level" - a choice of words that places further pressure on the ECB chief executive Tom Harrison, following his unconvincing display at last week's parliamentary hearing into the Azeem Rafiq racism scandal.

Leicestershire's vice-chairman, Jonathan Duckworth, is set to become interim chairman until a long-term replacement is identified.

"Cricket has been torn apart by recent events and I am deeply saddened by the hurt felt by individuals within our game," Duke said in her statement. "With fresh leadership at national level and with a determination to learn from the recent past and move forward, I hope that racism and discrimination will be expunged from the dressing rooms, the fields, and the game as a whole, allowing us to celebrate the diversity which makes cricket and sport in this country so great.

"I wish all of my colleagues on the board and across the network, the players, staff and the community teams, all the very best for the future," she added. "I thank the Members, supporters, and sponsors for their unwavering loyalty to the club and especially during some difficult times."

The news emerged as the ECB were forced to concede that their response to cricket's racism allegations, drafted at an all-stakeholders meeting at the Kia Oval last Friday, was "not quite there", having originally been expected to be finalised by Wednesday.

Once the final wording of the plan has been agreed, it is expected to include a commitment to a 30 percent boardroom representation for women and "representative ethnicities" at all first-class and national county clubs, as well as ongoing diversity training for all players, staff, umpires and coaches.

Meanwhile, Azeem Rafiq has met with a Holocaust survivor at the Jewish Museum in London, in the wake of his apology for anti-Semitic messages that he sent as a 19-year-old in 2011.

Rafiq, who is facing an ECB investigation for his comments - which included the suggestion that the Derbyshire player, Atif Sheikh, had been unwilling to spend money on a meal out because "he is a jew" - met with Ruth Barnett, who escaped Nazi Germany in 1939, as well as Steve Silverman from the Campaign Against Antisemitism.

In his apology, Rafiq had said: "I am incredibly angry at myself and I apologise to the Jewish community and everyone who is rightly offended by this," and has committed himself to education on the issue of anti-Semitism.