WASHINGTON (REUTERS) - US President Donald Trump left open on Wednesday (Sept 11) the possibility that the United States could ease sanctions on Iran, adding he believes Iran wants to strike a deal with Washington on its nuclear programme.

"We'll see what happens," Trump told reporters at the White House when asked about the possibility the United States would ease up on its "maximum pressure" campaign.

Trump's firing of his hard-line national security adviser, John Bolton, on Tuesday prompted speculation that Washington's policy towards adversaries such as Iran could ease.

Separately, Iranian President Hassan Rouhani said Teheran would not negotiate with Washington while sanctions on his country are still being enforced by Washington.

Trump said on Wednesday it would be "very very dangerous" for Iran to enrich uranium, a key step in developing a nuclear weapon, and also said, "I do believe they'd like to make a deal."

"If they do, that's great. If they don't, that's great too," he said.

"They have tremendous financial difficulty and the sanctions are getting tougher and tougher."

Trump and US Secretary of State Mike Pompeo have said the president is open to meeting with Rouhani, possibly at the United Nations General Assembly meeting later this month.

Asked if he was looking at such a meeting, Trump told reporters he was not looking at anything.