JERUSALEM >> A former top aide to Prime Minister Benjamin Netanyahu of Israel turned state’s witness today, the third close associate to agree to testify against him in a corruption scandal that threatens to end his career.

The deal came after days of feverish speculation in Israel that Netanyahu, beleaguered by police investigations and facing possible bribery charges, might call a snap election in hopes of a quick validation of public support.

News of the plea deal broke as Netanyahu was in Washington to meet with President Donald Trump, diminishing any hope the Israeli leader may have held that his role on the international stage would overshadow the scandals back home.

Netanyahu has denied any wrongdoing, but the accelerating pace of the investigations and the pileup of state witnesses are casting a cloud over his political future.

The latest government witness is Nir Hefetz, a former journalist who served as chief spokesman for Netanyahu from 2009 to 2011, and later returned to work as the Netanyahu family’s media adviser, a post he held until October 2017.

He signed a deal with the authorities, police said Monday, that is likely to yield damning evidence in at least one bribery case in which Netanyahu and his wife, Sara, are suspects, and possibly others.

Hefetz joins Shlomo Filber, a former director-general of the Communications Ministry, in cooperating with investigators in a case alleging that Netanyahu provided favors to Israel’s largest telecommunications company, Bezeq, in exchange for fawning coverage. Netanyahu was serving as minister of communications at the time.

On Friday, Netanyahu and his wife were questioned for hours about the case in separate locations — he in the official prime minister’s residence, she at the headquarters of the fraud investigations unit in central Israel. The police were reported to have surprised Sara Netanyahu by questioning her as a suspect, rather than just taking her testimony as a witness, and to have set up an elaborate six-way interrogation, questioning other main suspects, including Hefetz; Shaul Elovitch, the owner of Bezeq and a friend of Benjamin Netanyahu’s; and his wife, Iris, a friend of Sara Netanyahu’s, in separate rooms and feeding information to investigators.

Hefetz also has been implicated in another case, involving allegations that he sought, through an intermediary, to bribe a judge into dropping a separate criminal investigation involving the misuse of public funds by Sara Netanyahu.

The third state witness, Ari Harow, the prime minister’s former chief of staff and once one of his closest confidants, signed a deal with the police seven months ago and was expected to provide incriminating evidence in two other graft cases involving illicit gifts for favors and backroom dealings with a local newspaper magnate in another bid for favorable press coverage.

Last month, the police recommended that Benjamin Netanyahu be charged with bribery, fraud and breach of trust in both of those cases. Israel’s attorney general, Avichai Mandelblit, has yet to decide whether to issue an indictment, pending a hearing with Netanyahu’s lawyers, a process that can take months.

Netanyahu arrived in Washington on Sunday for meetings with Trump today and to address the American Israel Public Affairs Committee, a pro-Israel lobbying group, Tuesday. Netanyahu has a close relationship with Trump and has benefited at home from Trump’s decision to move the U.S. Embassy from Tel Aviv to Jerusalem.

Responding to the news of Hefetz’s deal with the authorities, a Netanyahu aide said in a statement: “When there is something there, you don’t need even one state witness. When you don’t have anything, even a thousand state witnesses won’t help. The incessant race after state witnesses is the best proof that there is nothing — and there will be nothing.”

Israeli pundits have been speculating for days on whether Netanyahu’s worsening legal situation would spur him to call an early election, given polls showing he still has the support of his voters. On Monday, however, they were raising the possibility that damaging testimony from Hefetz might dissuade him from the idea of rushing to the ballot box.

The new talk of early elections comes amid rising friction within Netanyahu’s coalition over an unrelated matter. The looming crisis involves a clash between two parties in the coalition over a proposed law formalizing the exemption of ultra-Orthodox youths from mandatory army service.

An ultra-Orthodox party insists on its passage before a vote on next year’s budget. The legislation does not appear to have the support of a majority in Knesset, since another party in the coalition opposes it.

Ministers from yet another party in the coalition, the far-right Jewish Home, have described the coalition squabbling as a “fake” crisis, indicating Netanyahu could resolve it if he wished.

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