The tough comments came shortly before Israel's trade minister headed to Turkey in what his office described as a mission meant to improve ties between the nations.

Turkey, a secular country ruled by an Islamic-oriented party, has long been Israel's best friend in the Muslim world, and it mediated months of indirect talks between Israel and Syria last year.

But ties have frayed badly since Israel's military offensive in the Gaza Strip last winter, where about 1,400 people were killed. Turkey has complained about the steep Palestinian civilian death toll. Syria-Israel talks were another casualty of the war, breaking down after little tangible progress.

On Sunday, Israeli Foreign Minister Avigdor Lieberman denied an Israeli newspaper report that Prime Minister Benjamin Netanyahu wanted Turkey to resume its role as mediator in exchange for the restoration of cordial ties.

"After all their invective and nonsense ... they cannot be mediators," Lieberman said. Much of that invective has been delivered by Turkish Prime Minister Recep Tayyip Erdogan.

In January, Erdogan stormed off a stage he shared with Israeli President Shimon Peres at the World Economic Forum in Davos, Switzerland, after telling Peres, "You kill people."

On another occasion, Erdogan said Israel's crimes in Gaza were worse than Sudan's in Darfur, where hundreds of thousands have been killed and millions made homeless. Erdogan refused to discuss the issue with Netanyahu, but he said he was prepared to talk to Sudanese leader Omar al-Bashir, who is facing war crimes charges filed by the International Criminal Court.

Earlier this month, Netanyahu also questioned Turkey's credentials, reportedly telling his Cabinet that Erdogan could not be a "fair mediator."

The comments came as Israel's trade minister, Binyamin Ben-Eliezer, prepared to head to Turkey on Sunday for a two-day working visit. His office said Ben-Eliezer would raise the issue of restarting Turkish-mediated talks with Syria.

"Of course we're going to talk about Syria. We're supposed to talk about Syria and Syrian talks with Israel," said Ben-Eliezer's spokesman, Asaf Azulai.

Turkey and Israel grew close in the mid-1990s, their alliance based on mutual fears of Iran, Iraq and Syria.

But since Erdogan's more Islamist-oriented government came to power in 2003, Turkey's ties with Israel have cooled.

Ties deteriorated further after Turkey called off an international military drill last month because it opposed Israel's participation.