The U.S. administration has been "deliberately provoking" Iran in order to destroy the nuclear arrangement and impose its own objectives, the former British ambassador to Iran told CNBC Tuesday.

Speaking to CNBC's "Street Signs Europe," Richard Dalton said objectives laid out by U.S. Secretary of State Mike Pompeo required Iran to "surrender all its national interests in the Middle East" and to "change the nature of its regime."

"It's an intolerable proposition to put to Iran and it's not surprising, and the United States will have calculated this long ago when they took the steps that they have taken, that Iran should have retaliated in accordance with its long-term policy, which is that if the Persian Gulf can't be used freely by everyone to export oil, then why should anybody export oil in security from that area?" Dalton said.

A State Department spokesperson said in response that the administration wants Iran to behave like a "normal nation."

"The president made clear he was ready to talk without preconditions when the circumstances are right," the spokesperson said. "The United States is seeking a deal with Iran that comprehensively addresses the regime's destabilizing behavior — not just its nuclear program but also its missile program, support for terrorist proxies, and malign regional behavior."

President Donald Trump on Monday struck a softer tone on Iran, assuring that the White House was not looking for regime change and suggesting that a new Iran deal could be struck quickly.

Trump also said he would agree to meet with Iranian President Hassan Rouhani "if the circumstances were right."

Washington wants a fresh agreement which would place indefinite curbs on Iran's nuclear program and halt its development of ballistic missiles, requests Tehran has thus far rejected.