(Reuters) - Henry Birch, the former chief executive of Rank Group, is among the contenders to become the head of British gambling group Entain, Sky News reported on Saturday, citing unidentified sources.

The Ladbrokes owner is searching for a new CEO after the abrupt departure of Jette Nygaard-Andersen in December following reports of shareholder and investor dissatisfaction at Entain's sluggish business performance.

In her resignation statement, Nygaard-Andersen said the group was "safe, stable and sustainable".

Entain said last month that its chairman, Barry Gibson, would step down by the end of September after more than four years in the role.

The betting group reported a smaller-than-expected fall in online gaming revenue for the first quarter, as an increase in active customers helped it offset stiff competition and regulatory pressures in its main markets.

Entain declined to comment on the Sky report.

(Reporting by Akanksha Khushi in Bengaluru; Editing by Alison Williams)