Israel and Syria are holding indirect peace talks, with Turkey acting as a mediator, both countries confirmed officially for the first time today.

The nations have "indicated they want to lead these negotiations in a serious spirit so as to reach a comprehensive peace agreement", a spokesman for Israel's prime minister, Ehud Olmert, said.

Syria's foreign ministry confirmed the country was holding "indirect peace talks with Israel under Turkish auspices", Reuters reported.

The brief statements mark the first official acknowledgment that the countries – which have fought three conflicts in Israel's 60-year history and remain officially at war - are talking again about the tangled issue of the Golan Heights, captured by Israel in the 1967 six day war.

There have been repeated recent reports of such indirect talks. Syria's president, Bashar Assad, told a Qatari newspaper last month that Turkey, which has good relations with both nations, had been assisting with talks for the past year.

The last talks over the Golan Heights, mediated by the US, broke down in 2000 over disagreements as to how far Israel should withdraw from the territory.

Another Israeli government official, speaking anonymously, said today that Olmert's chief of staff and diplomatic adviser had been in Turkey since Monday, as had their Syrian counterparts. He gave no details of any talks.

Turkey's NTV television said that while both delegations were in Istanbul they did not meet directly, but that Turkish mediators were shuttling between them.

According to Olmert's spokesman, contact began in February 2007 when the Israeli prime minister visited Turkey.

"In the discussions, the issue of Syria came up, and the Turks started to play a role that was designed to try to create a political momentum between Israel and Syria," said the spokesman, Mark Regev.

The indirect contacts have seemingly continued even after Israeli military planes attacked an installation in Syria in September last year. Israel has refused to comment on the raid but the US said last month that the target was an unfinished Syrian nuclear plant being built with North Korean assistance.

In his comments to the Qatar-based al-Watan newspaper last month, Assad said the Turkish-brokered talks had seen Israel offer to withdraw from the Golan Heights in return for a peace treaty with Syria, but that there would be no direct negotiations between the nations until a new US president took office next year.

It is unclear how much of the Golan Heights Israel is willing to cede, or the extent of withdrawal demanded by Syria.

In the past, Syria has demanded the return of the whole of the territory, including a narrow strip along the Sea of Galilee, Israel's main water source, a concession rejected by Israel.

As well as providing a guarantee of peace from Syria, a deal over the Golan Heights could help tempt Damascus from its currently close ties with Iran, a major regional foe for Israel.

However, it could prove politically difficult for Olmert, who faces a series of domestic political difficulties and is under pressure not to make significant territorial concessions to any of Israel's neighbours.

One recent opinion poll showed two-thirds of Israelis opposed the return of the Golan Heights, even in exchange for a promise of peace.

One group representing some of the 18,000 Israeli settlers living in the territory called the talks "a deluded and irresponsible move which would hand over such a vital Israeli strategic asset to the Arab axis of evil."

Olmert has also been weakened by recent claims about alleged corruption. Police have seized documents relating to Olmert's time both as mayor of Jerusalem and trade minister after reports he accepted bribes from an Jewish-American businessman.

The Israeli leader admits he accepted campaign donations from Morris Talansky but says he took no money for himself.