Israeli police on Tuesday named the two close associates of Prime Minister Benjamin Netanyahu who have been arrested for their suspected role in a wide-ranging corruption probe that has cast a further pall of suspicion over the longtime Israeli leader.

The development is the latest in scandals embroiling Netanyahu, who already stands accused of bribery in two separate cases. He denies any wrongdoing and says the accusations were the continuation of a wider witch hunt against him by a hostile media.

With an initial gag order lifted, police identified the pair as Nir Hefetz, a former Netanyahu spokesman, and Shlomo Filber, the former director of the communications ministry under Netanyahu.

The two are suspected of promoting regulation worth hundreds of millions of dollars to Israel's Bezeq telecom company in return for favourable coverage of Netanyahu in a highly popular subsidiary news site.

Netanyahu, who held the communications portfolio until last year, has not yet been named as a suspect in the case but is expected to be questioned.

Bezeq's controlling shareholder Shaul Elovitch is also in custody, along with his wife, son and other top Bezeq executives. Former journalists at the Walla news site have attested to being pressured to refrain from negative reporting of Netanyahu.

The new probe comes days after police announced there was sufficient evidence to indict Netanyahu for bribery, fraud and breach of trust in two separate cases.

Netanyahu is accused of receiving lavish gifts from Hollywood mogul Arnon Milchan and Australian billionaire James Packer. In return, police say Netanyahu had operated on Milchan's behalf on United States' visa matters, legislated a tax break and connected him with an Indian businessman.

In the second case, Netanyahu is accused of offering a newspaper publisher legislation that would weaken his paper's main rival in return for more favourable coverage.

Netanyahu has long accused the Israeli press corps of being biased against him and has taken steps to counter it by promoting more sympathetic outlets to him.