Turkey denied Thursday a U.S. newspaper report claiming it had blown an Israeli spy ring working with Iranians on its soil to the authorities in Tehran, a sign of the strained ties between the once close allies.

Washington Post columnist David Ignatius said Prime Minister Recep Tayyip Erdogan's government had last year revealed to Iranian intelligence the identities of up to 10 Iranians who had been meeting in Turkey with Mossad handlers.

The world's positive response to the latest nuclear talks with Iran drew bitter skepticism from Israel, which warned its Western allies Thursday they risked being duped into easing sanctions prematurely.

Energy Minister Silvan Shalom, a former foreign minister, went further, accusing the European Union and the United States of being more interested in the resumption of Iranian oil exports than with addressing an issue that Israel regards as a threat to its very existence.

Construction starts in Jewish settlements on occupied Palestinian land rose by a "drastic" 70 percent year-on-year in the first half of 2013, an Israeli NGO said on Thursday.

According to figures released by the anti-settlement group Peace Now, between January and June construction started on 1,708 new homes in the West Bank, including annexed east Jerusalem, compared with 995 in the first half of 2012.

The world must judge Iran's intentions by its actions and not by its "presentations" at the latest talks on its disputed nuclear program, a senior Israeli official said on Thursday.

"Iran will be judged by its actions and not by its presentations," the official said on condition of anonymity, in remarks just hours after world powers wrapped up two days of talks which the United States described as showing a new level of "seriousness".

Israel kept up its alarmist rhetoric on talks between world powers and Iran Wednesday, with a cabinet minister comparing the situation to pre-war Europe and the appeasement of Nazi Germany.

"We view the nuclear talks in Geneva with hope and with concern. We see the worrying signs and we don't want Geneva 2013 to turn into Munich 1938," International Relations Minister Yuval Steinitz said in remarks broadcast by Israel's army radio.

Israel on Tuesday urged the world to avoid a partial deal with Iran which could see a relaxing of sanctions, as a new round of nuclear talks were launched in Geneva.

The security cabinet warned the international community against any "partial agreement that would fail to bring about the full dismantling of the Iranian military nuclear program...(which) could lead to the collapse of the sanctions regime."

Shimon Peres says Israel and its allies must retain a firm stance on Iran until it can show it does not threaten regional stability, despite its election of Hassan Rouhani as president.

In an interview published Monday by the Brazilian newspaper the Folha de Sao Paulo, the Israeli president poured cold water on Rouhani's recent charm offensive.

Israel's army has agreed to test alternative treatment for Palestinian children it arrests in the West Bank following international pressure to introduce reforms, the U.N. Children's Fund said on Monday.

UNICEF, which in a March 2013 report described mistreatment of children in Israeli prisons as "widespread," said in a statement that Israel was taking steps towards addressing that report's recommendations.

Easing pressure on Iran over its nuclear program at this stage would be a "historic mistake," Israeli Prime Minister Benjamin Netanyahu said on Monday.

"It would be a historic mistake to ease the pressure on Iran a moment before the sanctions achieve their objective," he said at the opening of the Israeli parliament's winter session.

The Israeli intelligence minister called on the major powers on Monday to maintain pressure on Iran, saying that was what was driving it to seek a deal in nuclear talks.

Yuval Steinitz, who is also minister for international relations, was speaking on the eve of revived negotiations on Tehran's controversial nuclear program between Iranian officials and the P5+1 group of Britain, China, France, Russia and the United States, plus Germany.