World leaders have welcomed the “historic” nuclear accord between Iran and the great powers known as the 5+1 group.

“I warmly welcome the historic agreement in Vienna today and congratulate the P5+1 and Iran for reaching this agreement,” UN chief Ban Ki-moon said in a statement on Tuesday.

“This is testament to the value of dialogue,” Ban added.

He expressed the UN’s readiness to fully cooperate with the negotiating parties in the process of “implementing this historic and important agreement.”

The UN chief also said the nuclear deal could help improve peace in the Middle East.

“I hope -- and indeed believe -- that this agreement will lead to greater mutual understanding and cooperation on the many serious security challenges in the Middle East,” Ban said.

“As such, it could serve as a vital contribution to peace and stability both in the region and beyond,” he added

International Atomic Energy Agency Director General Yukiya Amano on Tuesday expressed confidence that the agency would be able to verify Iran’s activities under the Vienna nuclear deal.

“I am confident in our ability to do this important work. The IAEA stands ready to undertake the necessary monitoring and verification activities when requested,” the UN nuclear agency’s chief said in a statement.

------ NATO calls nuclear deal a ‘historic breakthrough’-------

NATO hailed the Iran nuclear deal on Tuesday as a “historic breakthrough” that would strengthen global security, but urged Tehran to comply with the terms of the accord, Defense News reported.

The deal sealed in Vienna aims at ensuring Iran does not obtain the nuclear bomb, relieving sanctions against Tehran and ending decades of tension with the West.

“This agreement represents a historic breakthrough which, once fully implemented, will strengthen international security,” said the U.S.-led military alliance's Secretary General Jens Stoltenberg.

“It is critical for Iran to implement the provisions of today's agreement and to fulfil all its international obligations and advance security in the region and beyond,” the former Norwegian premier added.


--------- Hollande calls the deal ‘very important’

French President Francois Hollande hailed the pact “very important.”

“It’s a very important deal that was signed overnight, the world is making headway,” Hollande said in his traditional annual televised interview on France’s national day.

----------- Britain hopes deal would be a ‘step-change’ in Tehran’s ties with outside world-------

British Foreign Secretary Philip Hammond hailed the “historic agreement” between Iran and the six global powers, expressing hope it would be “a step-change” in Tehran’s regional and international relations.

“We hope, and expect, that this agreement will herald a step-change in Iran’s relations with its neighbors and with the international community,” Hammond said in a statement.

-------Russia says 5+1 and Iran make ‘firm choice for stability and cooperation’---

On Tuesday Russian President Vladimir Putin also commended the conclusion of talks between Iran and the six world powers, saying the nuclear negotiating parties made a “firm choice for stability and cooperation.”

“Despite attempts to argue in favor of scenarios of force, the participants of the talks made a firm choice for stability and cooperation,” Putin said in a statement published on the Kremlin’s website.

He added that after the sides’ negotiations succeeded in reaching a conclusion, “the world has breathed a huge sigh of relief.”

The Russian president said his country would “do everything in its power” to ensure that the deal would work.

“We expect that all of the interested parties, primarily the 5+1 countries, will fully adhere to the decisions that have been reached,” Putin said.

Russian Foreign Minister Sergei Lavrov also told reporters in Vienna that Moscow will be “actively participating in the practical steps for the realizations of the agreement.”

The chief Russian diplomat emphasized that the Vienna deal “without a doubt will play an important role in ensuring non-proliferation in general” and “make the situation in the Middle East healthier.”

“A Joint Comprehensive Plan of Action consisting of the main document and five technical and totally specific annexes has been coordinated, and a draft resolution of the Security Council which all negotiating parties will submit for consideration by the UN Security Council as co-authors has been coordinated too,” he added.

He said the landmark deal would lead to further expansion of Tehran-Moscow business ties, including in the nuclear industry.

“We have great plans to develop Iran’s nuclear energy,” Lavrov said.

--------Hillary Clinton tells Democrats ‘it’s a deal worth supporting’ ---------

Hillary Rodham Clinton unequivocally embraced the Iran nuclear deal in a meeting with House Democrats at the Capitol on Tuesday, according to people who were at the meeting.

According to notes taken by one Democrat and given to The New York Times, Mrs. Clinton, who was secretary of state from 2009 to 2013, told them the deal is “not perfect,” but its core provisions are sound. She said, “It’s a deal worth supporting.”

Earlier in the day, Mrs. Clinton, a former senator from New York who is running for president in 2016, lauded the American negotiators.