German Vice Chancellor Sigmar Gabriel will lead a business delegation to Iran from Sunday, his ministry said a day after world powers and Tehran reached a historic nuclear deal.

Gabriel, who is also economy and energy minister, "will travel to Iran from July 19 to 21 with a small delegation of industry and science representatives," a ministry spokeswoman said in a statement to AFP.

U.S. President Barack Obama sought Wednesday to defend a ground-breaking deal to curb Iran's nuclear program from a tide of criticism, saying "profound differences" would remain with the Islamic republic.

Amid fears Washington was seeking to cozy up to its long-time foe with an agreement that might not stand the test of time, Obama said: "Even with this deal, we will continue to have profound differences with Iran." 

Arab League chief Nabil al-Arabi said Wednesday a historic nuclear deal between Iran and world powers is a first step to ridding the Middle East of weapons of mass destruction.

The head of the Cairo-based pan-Arab bloc expressed hopes the accord reached on Tuesday would usher in "stability and security" in the volatile region.

The March 14 General Secretariat on Wednesday congratulated the Iranian people, especially the “reformist movement,” on the nuclear deal that was reached with world powers, hoping the agreement will lead to Hizbullah's “return to the Lebanese state.”

“The General Secretariat congratulates the friendly Iranian people, and the reformist movement, which has triumphed through managing to shift Iran from investing in the 'export of the revolution' and sponsoring violence and terrorism to investing in stability, economic prosperity and commercial competition,” it said in a statement issued after its weekly meeting.

British Foreign Secretary Philip Hammond said he was heading to Israel later Wednesday to explain the Iran nuclear deal in person and voiced hope Britain could reopen its embassy in Tehran this year.

Briefing parliament about the agreement unveiled on Tuesday, Hammond said he would speak to Israeli Prime Minister Benjamin Netanyahu on Thursday "to convey our message about this deal directly".

Israeli Prime Minister Benjamin Netanyahu suffered a major defeat in failing to stop a nuclear deal with Iran but he remains as defiant as ever even at the risk of further isolation.

While the world's major powers welcomed the deal finalized with Iran on Tuesday as a historic moment capable of setting relations with the Islamic republic on a new path, Netanyahu harshly condemned it.

A chiefly U.S.-led nuclear deal between world powers and Iran has been held up as a harbinger to re-establishing formal relations but historical enmity makes broader detente a difficult prospect.

Both nations have reasons for distrust and a legacy of differences live on in the chants of "Death to America" that ring out at public ceremonies, even parliament, in the Iranian capital.

Iran's nuclear deal with world powers is a sign of a common will to end conflict in the region and defeat the Islamic State jihadist group, Iraq's premier said Wednesday.

"Daesh seeks to drag our region into perpetual conflict," Haider al-Abadi said on social media, using an Arabic acronym for IS.

A deal with world powers ended a "manufactured crisis" over Iran's nuclear program, its foreign minister said Wednesday as he arrived home from negotiating the agreement which angered U.S. lawmakers.

As attention turned to the lengthy process of implementing the complex accord, Mohammad Javad Zarif said the world had no cause to fear Iran's nuclear activities.

France's foreign minister said Wednesday he had accepted an invitation to visit Iran after the historic deal on its nuclear program but did not give a date for the trip.

Laurent Fabius said his Iranian counterpart Mohammad Javad Zarif had "reinvited" him as the deal was clinched on Tuesday.