With only three days to go before the Knesset election, Prime Minister Benjamin Netanyahu accused the opposition Zionist Union of running an illegitimate election campaign in a Facebook post on Friday.

"Left-wing and media elements in Israel and abroad have conspired to bring [Zionist Union leaders Isaac Herzog and Tzipi Livni] to power illegitimately, by means of slander at home and unprecedented money from abroad," Netanyahu wrote.

The prime minister also lashed out Yedioth Ahronoth newspaper, accusing it of running an intensive campaign against himself and his Likud party in collaboration with unnamed organizations, NGOs, tycoons and foreign governments.

"Numerous testimonies by Yedioth Ahronoth employees that have reached us recently indicate that [Yedioth Ahronoth publisher] Noni Mozes is leading an orchestrated campaign against the Likud and against me, in collaboration with organizations and NGOs that are acting for that purpose with the support of tycoons in Israel and abroad and also the support of foreign governments," Netanyahu wrote.

He went on to accuse the newspaper of "cooperating and coordinating fully" with the leaders of Zionist Union. The Zionist Union platform, he added, "implicitly commits" the party to closing down Yisrael Hayom, a newspaper that supports the prime minister.

"The public needs to know the truth," Netanyahu wrote. "Noni Mozes is leading a campaign against the Likud and against me out of commercial interests, with the objective of reviving the dangerous and undemocratic monopoly it enjoyed in the past."

"The goal of Mozes is to bring about the rise of the left. He is joined by left-wing elements in Israel and abroad who are streaming tens of millions of dollars to NGOs running an 'Anyone but Bibi' campaign in its various guises."

"Those NGOs are encouraging higher voter turnout among the Arab population and left-wing voters, including by means of a grassroots campaign going from door to door."

The reason for the mobilization of the unnamed NGOs, the prime minister said, was not social or economic – but diplomatic: To bring about "a withdrawal to the '67 lines, the division of Jerusalem, the establishment of Hamastan B on the heights overlooking Tel Aviv and Ben-Gurion Airport and Israeli acceptance of a nuclear Iran."

"The rule of the right is in danger," Netanyahu wrote, adding that the only way to ensure that the left does not succeed is to "close the gap in the days that remain before the election."

Voters from the "nationalist camp," the prime minister said, "don't have the privilege of voting for other parties. They have to vote Mahal (the acronym used by Likud on the ballot forms.) Victory for the Likud is the best and only answer to the tricks of the left."