The Trump administration is urging Europe to impose tough new sanctions on Iran over its ballistic missile program.
The call comes as U.S. Secretary of State Mike Pompeo was preparing to meet with European officials in Brussels this week and after the U.S. and others condemned an Iranian missile launch over the weekend.
Iran was also discussed in a meeting Monday between Pompeo and Prime Minister Benjamin Netanyahu in Brussels.
Pompeo plans to talk about Iran when he meets his counterparts from Britain, France and Germany on Tuesday while he is in Belgium for a meeting of NATO counterparts.
U.S. special envoy for Iran Brian Hook rejected Iran's insistence that its missile program is defensive.
He told reporters traveling with Pompeo that Iran's continued missile development and testing is a threat to the region and beyond and in defiance of U.N. Security Council demands.
Hook said U.S. discussions with the Europeans about missile sanctions are gaining traction. Those talks center on slapping penalties on companies and people involved in Iran's program.
"It is a grave and escalating threat, and nations around the world, not just Europe, need to do everything they can to be targeting Iran's missile program," Hook said.
Hook's comments on Monday were the latest salvo in an escalating U.S. campaign against Iran since President Donald Trump pulled out of the 2015 nuclear deal in May.
"Iran is on the wrong track, and our campaign of maximum economic pressure is designed to starve the regime of revenue it needs," he said.
On Thursday, Hook accused Iran of violating a U.N. ban on Iranian arms exports by sending weapons to its proxies in Afghanistan, Iraq, Lebanon, Syria and Yemen.
On Saturday, Pompeo denounced Iran for test-firing a medium-range ballistic missile capable of carrying multiple warheads that could reach parts of Europe.
"We are accumulating risk of escalation in the region if we fail to restore deterrence," Pompeo said.
Also on Monday, Iranian Oil Minister Bijan Zanganeh said that the Islamic republic's oil industry was on the frontline of the fight against "the enemy," adding that Tehran would do its utmost to counter U.S.-led efforts to put economic pressure on the country.
Zanganeh, in comments reported by SHANA, the oil ministry's news agency, did not specify who he saw as the enemy but Iran is locked in confrontation with the United States, which has applied sanctions and has said that its goal is to reduce Iran's oil exports to zero.
"The oil, gas and petrochemical sectors are the front line in the battle against the enemy," Zanganeh said.
President Donald Trump pulled the United States out of a multilateral nuclear deal with Iran in May and reimposed sanctions on Iran's oil industry last month.
The Iranian government's most important role is to reduce the economic difficulties of ordinary Iranians brought about by American pressure, Zanganeh said.
"The goal of America and its regional allies is, through exerting pressure and economic shortages, to say we have hit a dead end on the threshold of the 40th anniversary of the Islamic revolution," Zanganeh said.
"We have a legal and religious duty to reduce the income pressure on the people. This is the most important thing that we must do and the government is putting forth all its efforts on this issue."
