(Adds comments by Olmert spokeswoman, paragraphs 9-11)
JERUSALEM, Oct 17 (Reuters) - Israeli Prime Minister Ehud Olmert will hold talks in Russia with President Vladimir Putin on Thursday, the Israeli leader's office said on Wednesday, announcing the surprise visit.
"The prime minister intends to discuss with the Russian president a series of regional issues including the peace process with the Palestinians and Iran's threats and its attempt to equip itself with nuclear weapons," the announcement said.
A visit by Putin to Tehran on Tuesday was watched closely because of Moscow's possible leverage in the Islamic Republic's nuclear row with the West.
During the visit, Putin made clear to Washington that Russia would not accept military action against Iran and he invited Iranian President Mahmoud Ahmadinejad to Moscow for talks.
Iran says its nuclear programme is for peaceful purposes.
Western powers fear Iran's pursuit of nuclear-generated electricity is a precursor to it learning how to build atom bombs. They have sponsored two sets of U.N. sanctions against Tehran and are preparing to draft harsher penalties.
Olmert will return to Israel on Thursday evening after his meeting with Putin, the prime minister's office said.
Olmert last visited Moscow a year ago and voiced Israel's concerns about Iran's nuclear ambitions in talks in the Kremlin with Putin.
Miri Eisin, Olmert's spokeswoman, said she was sure Putin's visit to Iran would be discussed but it had not prompted the visit.
She said Olmert and Putin had spoken on the phone last Wednesday and they said, "Let's meet sooner rather than later".
The leaders decided to hold talks on Thursday because if they had waited until later it would have been impossible to schedule the meeting until next year, Eisin said.
News of the Olmert's planned trip came on the final day of a four-day visit to Israel and the occupied West Bank by U.S. Secretary of State Condoleezza Rice, who is preparing the ground for a U.S.-sponsored Middle East conference expected next month.