US President Barack Obama said today the United States strongly supported the aim of setting up a Palestinian state living "side by side" and at peace with Israel.
Mr Obama reiterated the US position after Israel's new foreign minister said last week that Israel was not bound by a deal to start negotiations on establishing a Palestinian state.
"Let me be clear: the United States strongly supports the goal of two states, Israel and Palestine, living side by side in peace and security," Mr Obama said in a speech to the Turkish parliament.
"Now, we must not give into pessimism and mistrust. We must pursue every opportunity for progress," he said, weighing in on the Middle East peace issue for the first time since rightist Israeli Prime Minister Benjamin Netanyahu took power and formed a new government.
Mr Obama promised to actively pursue a resolution to the Israeli-Palestinian conflict.
"We know that the road ahead will be difficult. Both Israelis and Palestinians must take the steps that are necessary to build confidence," he said.
In his speech, Mr Obama also said he sought engagment with Iran.
But he added: "Iran's leaders must choose whether they will try to build a weapon or build a better future for their people."
Mr Obama also stood by his views on mass killings of Armenians by Ottoman Turks in 1915, which he has termed genocide, but said he expected a breakthrough in talks between Turkey and Armenia.
Ankara and Yerevan are engaged in negotiations aimed at restoring full diplomatic ties after nearly a century of hostilities, and may be on the point of reopening their border.
Mr Obama, asked about the historical controversy during a two-day visit to Turkey, said he had not changed his mind, but sought to shift the focus onto the Turkish-Armenian talks.
"My views are on the record and I have not changed those views," he told a joint news conference with Turkish President Abdullah Gul.
As a candidate, Mr Obama pledged to call the killings genocide, which Ankara rejects, and a resolution to so designate them was introduced in the US House of Representatives last month. The issue has hurt ties between the two NATO allies before.
"I want to be as encouraging as possible around those negotiations which are moving forward and could bear fruit very quickly, very soon, so as a consequence what I want to do is not focus on my views right now," Mr Obama said, seeking to strike a balance over the issue while adding pressure on the talks.
A breakthrough between Turkey and Armenia could help shore up stability in the volatile Caucasus, criss-crossed by oil and gas pipelines which make it of strategic importance to Russia, Europe and the United States.
Mr Gul, who has spearheaded talks between Ankara and Yerevan, also said he expected them to bear fruit soon.
Turkey closed its border with Armenia in 1993 in solidarity with Azerbaijan, which was fighting Armenian-backed separatists over the breakaway Nagorno-Karabakh region.
"When our government came to power there were almost no relations between Turkey and Armenia," Mr Gul said.
"Now we are in talks with Armenia to normalise relations. I hope these talks will yield the best possible result."
Azerbaijan, which fears a Turkish-Armenian rapprochement would weaken its hand in the Nagorno-Karabakh dispute, has said a decision by Ankara to open the border with Armenia before Yerevan withdraws its troops from the enclave would be "counter to Azerbaijan's national interests".
Turkish officials have warned that any new attempt in Congress to brand the killings as genocide could damage US-Turkish ties and derail the Turkish-Armenian talks.
Mr Obama is in Turkey to rebuild ties with the Muslim country, whose help he needs to solve confrontations from Iran to Afghanistan.
Turkey accepts that many Christian Armenians were killed by Ottoman Turks during World War One but strongly denies that up to 1.5 million died as a result of genocide.
Reuters