A former judge of Israel's highest court does not expect Prime Minister Benjamin Netanyahu, who is accused of corruption, to be pardoned.

Ex-judge Izchak Zamir told the Israeli Kan channel that President Izchak Herzog would be breaking the law if he granted such a pardon.

"That is why I believe that he will not grant a pardon as long as the head of government does not admit in writing to the offences attributed to him," said the former judge.

A presidential pardon has been granted in Israel only once before. The persons concerned had not been convicted in court, but they had previously admitted their guilt.

It is unclear when Herzog will decide on Netanyahu's highly controversial request for clemency. In the meantime, he has received an expert opinion from the Ministry of Justice.

Netanyahu submitted the petition for clemency in November. Among other things, he cited fierce disputes in Israel over his corruption trial, which has been running for almost six years. The prime minister is accused of fraud, breach of trust and bribery.

The former judge expressed great concern about efforts by Netanyahu's government to weaken the judiciary in the country. "Three years ago, the government began a campaign to destroy democracy," said Zamir.

In the meantime, he said, Israel has almost reached the point of autocratic rule by Netanyahu.

"The prime minister controls the government and the government controls the parliament," he said. There is no real separation of powers, as is necessary in a democracy.

All that is left is an independent judiciary, which he said they also want to destroy. Should this succeed, it would be "the end of democracy" in Israel, he warned.

Netanyahu's government argued that the court was too powerful and interfered too much in political issues, and that they merely wanted to restore a balance.