Despite welcome and laud from the international community, the framework agreement also met with skepticism, even opposition, in particular from Israel, a bitter rival of Iran.

During a telephone conversation with Obama late Thursday, Israeli Prime Minister Benjamin Netanyahu said the deal "poses a grave danger to Israel, the region and the world," his office said in a statement.

"A deal based on this framework would threaten the survival of Israel," he said, adding that the deal would also "legitimize Iran's nuclear program, bolster Iran's economy, and increase Iran's aggression and terror throughout the Middle East and beyond."

"Such a deal would not block Iran's path to the bomb. It would pave it," he continued. "It would increase the risks of nuclear proliferation in the region and the risks of a horrific war."

Prior to Netanyahu's remarks, Israeli Intelligence Minister Yuval Steinitz said the framework agreement is "far from being real," adding that Israel will "continue its efforts in the hopes of preventing a bad deal."

"All options are on the table" in order to prevent Iran from reaching nuclear weapons, including a military option, the minister said in an interview with Israel Radio.

Meanwhile, Saudi Arabia, Iran's key regional rival, and other Gulf Arab states remained silent about the deal.

A senior Gulf Arab official said any reaction would come in the days ahead, not from individual countries but from the Gulf Cooperation Council (GCC), an alliance of Saudi Arabia, Kuwait, the United Arab Emirates (UAE), Qatar, Oman and Bahrain.

In Washington, US House Speaker John Boehner slammed the agreement as an "alarming departure" from the White House's initial goals, suggesting the Obama administration caved in to Iranian negotiators and allowed certain concessions.

"My immediate concern is the administration signalling it will provide near-term sanctions relief," he said in a statement. "Congress must be allowed to fully review the details of any agreement before any sanctions are lifted."

Mindful of skeptics at home and abroad, Obama warned that only a negotiated deal can prevent Iran from building a nuclear bomb.

"If Congress kills this deal not based on expert analysis, and without offering any reasonable alternative, then it's the United States that will be blamed for the failure of diplomacy," the president said.

"International unity will collapse, and the path to conflict will widen," he added.

Analysts said that as a proper agreement is the only way to guard against a nuclear armed Iran and provide meaningful sanctions relief, both Western countries and Tehran should take substantial actions to overcome decades of mistrust.

Admitting that many technical details need to be worked out on both sides, US Secretary of State John Kerry said there is still a long way to go in the next three months.

"We still have a way to travel before we'll arrive at the destination that we seek," he said.