U.S. Secretary of State John Kerry urged Turkish leaders Sunday to speedily restore full diplomatic relations with Israel, two American allies the U.S. sees as anchors of stability in a Middle East wracked by Syria's civil war, Arab Spring political upheavals and the potential threat posed by Iran's nuclear program.

Turkey, however, demanded that Israel end all "embargoes" against the Palestinians first.

Syrian President Bashar Assad has warned that the fall of his regime would destabilize the region "for many years", as U.S. President Barack Obama announced talks with Middle East allies over the crisis.

"The whole world knows that if Syria is partitioned, or if terrorist forces take control of the country, there will be direct contagion of the surrounding countries," Assad said in an interview with two Turkish media outlets, video of which was posted on his Facebook page Friday.

President Barack Obama will host leaders from key U.S. allies Jordan, Turkey, Qatar and the United Arab Emirates in the coming weeks, amid turmoil in Syria, the White House said Friday.

The U.S. administration said Jordan's King Abdullah II will meet with Obama on April 26 for talks "Jordan's political and economic reforms, the humanitarian crisis in Syria, and additional regional issues of mutual concern."

Syrian President Bashar Assad accused Turkish Prime Minister Recep Tayyip Erdogan of not having said "a single word of truth" about Syria's conflict, in an interview with Turkish media posted on the web.

"Erdogan has not said a single word of truth since the beginning of the crisis in Syria," Assad told journalists working for Turkish television Ulusal and Aydinlik newspaper.

Turkey's parliament speaker called Thursday on political parties to draft a new democratic constitution without delay, warning that failure to do so would tarnish the country's image.

Political parties in the 550-seat parliament have been working since 2011 to replace the current constitution which was drafted by the powerful army after the 1980 military coup.

Amnesty International criticized Wednesday European Union hopeful Turkey's dismal record on freedom of expression and called for legislative reforms to bring "abuses to an end."

"Freedom of expression is under attack in Turkey," the London-based group said.

Turkey's government is planning to establish a consultative body to oversee the ongoing peace negotiations with the outlawed Kurdistan Workers' Party (PKK), the prime minister said on Tuesday.

"If we decide on forming a group of wise people... it will be our consultative committee," Prime Minister Recep Tayyip Erdogan told his lawmakers in a parliamentary meeting.

Israel and Turkey's recent rapprochement is a vital factor in developing peace and stability in the Middle East, U.S. Secretary of State John Kerry said.

U.S. President Barack Obama brokered the tentative reconciliation between Israeli Prime Minister Benjamin Netanyahu and Turkish Prime Minister Recep Tayyip Erdogan on Friday during his visit to Israel.

U.S. President Barack Obama strolled among the ancient Jordanian ruins at Petra on Saturday, on the final leg of a four-day Middle East tour dominated by his embrace of Israel.

Obama flew by helicopter to view the rose-colored stone ruins of the ancient Nabataean city, after winds from a sandstorm abated and allowed him to make the 55-minute trip across the plains and mountains of Jordan.

Turkey welcomed on Friday Kurdish rebel leader Abdullah Ocalan's ceasefire call as a crucial step towards peace, but obstacles remained in resolving a conflict that has torn the country for nearly three decades and killed around 45,000 people.

"This is the Spring of Turkey," declared the headline of liberal Taraf daily, printed on a picture showing the vast crowd of people who gathered on Thursday in the southeastern city of Diyarbakir to hear the message from jailed Ocalan.