International pressure was mounting on Israel on Thursday over its plans to add another 1,100 homes to the east Jerusalem settlement neighbourhood of Gilo.
The Palestinian leadership has said the move effectively rebuffs a proposal from the Middle East Quartet for fresh peace talks, though senior Israeli politicians have given the Quartet's plan a cautious welcome.
Former friend turned bitter critic Turkey said on Thursday that the construction plan further underlined the need for the world to back the Palestinian bid for full UN membership.
"Israel's decision raises serious doubts about its sincerity and its true intentions," Turkey's foreign ministry said in a statement. "It constitutes a flagrant violation of international law and is unacceptable."
Relations between Israel and Turkey have steadily deteriorated since May 2010, when an Israeli assault on an aid flotilla bound for the Hamas-ruled Gaza Strip left nine Turkish nationals dead.
On Wednesday, after the European Union and the United States condemned the Gilo project, China, Egypt, Russia and other major powers voiced their opposition.
"China deeply regrets and opposes Israel's approval of plans for expansion of Jewish settlements in east Jerusalem," foreign ministry spokesman Hong Lei told reporters in Beijing.
"China urges Israel to act prudently."
Egyptian Foreign Minister Mohammed Amr also denounced the plans in a statement issued from Washington.
"Such an Israeli step reflects the country's intention to continue with its provocative policy and defiance of the international consensus regarding the illegitimacy of settlement activities," he said.
"Israel should shoulder full responsibility for the repercussions of such provocative policies in light of the latest developments in the region," he added.
Russia called on Israel to reconsider.
Signup to our newsletter and follow us on Facebook and Twitter!
"We are particularly concerned that decisions on such a sensitive matter should be taken at an extremely important time for the future of the peace process," the Russian foreign ministry said in a statement.
"We are counting (on Israel) so that the construction projects in east Jerusalem are reviewed."
Britain, France and Italy also condemned the move, but Israel dismissed their objections.
"Gilo is not a settlement, nor is it an outpost," Mark Regev, a spokesman for Israeli Prime Minister Benjamin Netanyahu told AFP on Wednesday.
"Gilo is a neighbourhood in the very heart of Jerusalem some five minutes from the centre of the city," he added.
"There is no contradiction between this decision, which is only a planning decision, and the government's pursuit of peace through the principle of two states for two peoples."
Palestinian leaders have nevertheless insisted it marks a snub to moves by the Middle East Quartet -- the United Nations, the European Union, the United States and Russia -- to restart talks between Israel and the Palestinians.
"With this, Israel is responding to the Quartet's statement with 1,100 'Nos'," Palestinian negotiator Saeb Erakat told AFP on Tuesday, shortly after the approval was made public.
It was Israel's refusal to freeze building that prompted the Palestinian decision to seek UN membership in a bid to gain broader international support for a two-state solution.
That proposal is currently before the UN Security Council.
Netanyahu has already said he favours the Quartet proposal, which calls for the immediate resumption of direct talks "without preconditions."
Peace talks between Israel and the Palestinians ran aground last autumn in a dispute over Jewish settlement building on land the Palestinians want for their future state.
The Palestinians insist they will not return to peace talks without a freeze on settlement activity or reference to the 1967 lines as the basis for talks, and have yet to respond officially to the Quartet proposal.
Palestinian president Mahmud Abbas was on Thursday meeting the executive committee of the Palestine Liberation Organisation to discuss the Quartet's proposal and the UN membership move.