JERUSALEM: Israel's attorney general on Thursday charged Foreign Minister Avigdor Lieberman with fraud and breach of trust, barely five weeks before a snap election, but dropped more serious allegations against him.

Although the announcement prompted immediate opposition calls for his resignation, the controversial politician's lawyers played down the charges, saying ministers charged with similar offences in the past had not stepped down.

“After examining the file, I have arrived at the conclusion that there is insufficient evidence to charge him in the first case and have decided to close it,” attorney general Yehuda Weinstein said in a statement.

But a lesser case, which includes allegations of fraud and breach of trust, would go ahead, he added.

“I decided to proceed with a case against Lieberman for having suggested in December 2009 that the government name the former ambassador to Belarus to a post in another country, despite the fact that, according to the evidence presented, he knew that he done wrong in passing along secret information, including details of a police inquiry against Lieberman,” he said.

The decision closes a case that included explosive allegations of fraud, money-laundering and witness tampering. Lieberman has always proclaimed his innocence of all the allegations against him.

While the closing of the main case against him is something of a victory for Lieberman, who leads the ultra-nationalist Yisrael Beitenu party, he still faces enormous pressure to resign over the charges, ahead of January 22 elections.

His party is running on a joint list with Prime Minister Benjamin Netanyahu's Likud faction, and is expected to win at least 38 seats in the 120-seat Knesset, far ahead of the opposition.

Shortly after Weinstein's announcement, the HaTnua party led by former foreign minister Tzipi Livni issued a statement calling on Netanyahu to force Lieberman's resignation.

“HaTnua calls on the prime minister to act according to the legal norms observed in Israel under which ministers who have been indicted immediately resign from the government,” it said.

“This is what is also expected from Lieberman.”

The Labour party warned of “the danger to Israeli democracy if Lieberman does not resign,” but Lieberman's lawyers noted that ministers charged with similar offences in the past had not stepped down.

And Lieberman's cabinet colleague, Education Minister Gideon Saar from Netanyahu's Likud faction, said he was disappointed that “Lieberman will be prosecuted over a marginal issue in an investigation that was closed.”

Weinstein made no specific recommendation on whether Lieberman should resign, and local media said the legal precedent was unclear.

The leftwing Meretz party has said it will go to court in a bid to force the foreign minister to step aside.

In the past, Lieberman had suggested he would resign if the main case against him went ahead, but with that case closed it was unclear if he would choose to step down.

He was expected to attend a campaign event later Thursday, and Netanyahu's office said it would have no comment until after Lieberman spoke.

The foreign minister has faced several investigations since 1996 on a number of fraud and corruption allegations but had never previously been charged.

A Soviet-born former bouncer, he has courted controversy with his hardline stance on Israel's Arab minority, with critics accusing him of racism.

A resident of the West Bank settlement of Nokdim, he pleaded guilty in 2001 to assaulting a Palestinian youth who had hit his son and has had regular verbal spars with Arab members of parliament.

He has also attracted criticism from Europe, where his strident views and undiplomatic language reportedly prompted former French president Nicolas Sarkozy to suggest to Netanyahu that he should fire Lieberman.