U.S. Democratic presidential front-runner Hillary Clinton on Wednesday called for sanctions against Iran after it brushed off U.S. concerns and test-fired two ballistic missiles that it said were designed to be able to hit Israel.

Iranian state television showed footage of two Qadr missiles being launched from northern Iran, which the Islamic Revolutionary Guards Corps (IRGC) said hit targets 1,400 kilometres away. Iranian agencies said the missiles were stamped with the Hebrew words, "Israel should be wiped from the pages of history," though the inscription could not be seen on any photographs.

Clinton, a former secretary of state under President Barack Obama, said she was "deeply concerned" by the tests, the second round of Iranian missile launches in two days.

"Iran should face sanctions for these activities and the international community must demonstrate that Iran's threats toward Israel will not be tolerated," said Clinton, who is ahead in the race to be Democratic nominee in the Nov. 8 presidential elections.

Democratic U.S. presidential hopeful Hillary Clinton, pictured at a campaign rally Tuesday, said Wednesday that Iran should face sanctions after Iranian media reported it had test-fired two ballistic missiles. (Aaron Josefczyk/Reuters)

Her call for sanctions reflected a tougher line against Iran's recent missile activity than that taken so far by the White House, which said it is aware of and reviewing reports of the Iranian tests, and would determine an appropriate response.

"We know that Iran is in a season of carrying out a number of military activities, and so it certainly would not be a surprise if there are additional launches over the next several days," White House spokesman Josh Earnest said.

The Iranian move on Wednesday came despite warning from the U.S. State Department after Tuesday's missile tests that Washington continues to "aggressively apply our unilateral tools to counter threats from Iran's missile program," a possible reference to additional U.S. sanctions.

U.S. Secretary of State John Kerry spoke on Wednesday with Iran's foreign minister about the test-firing of two ballistic missiles, a State Department spokesman said. The missile tests underline a rift in Iran between hard-line factions opposed to normalizing relations with the West, and President Hassan Rouhani's relatively moderate government, which is trying to attract foreign investors to Iran.

'Making a mockery'

Iran's IRGC said the missiles tested on Wednesday were designed with Israel in mind.

"The reason we designed our missiles with a range of 2,000 kilometres is to be able to hit our enemy the Zionist regime from a safe distance," Brigadier General Amir Ali Hajizadeh was quoted as saying by the ISNA agency. The nearest point in Iran is around 1,000 kilometres from Tel Aviv and Jerusalem.

Israeli Defence Minister Moshe Yaalon told Israel Radio the tests showed Iran's hostility had not changed since implementing a nuclear deal with world powers in January, despite Rouhani's overtures to the West.

"To my regret there are some in the West who are misled by the honeyed words of part of the Iranian leadership while the other part continues to procure equipment and weaponry, to arm terrorist groups," Yaalon said.

Representative Ed Royce, the Republican chairman of the U.S. House of Representatives' Foreign Affairs Committee, said: "Iran is making a mockery of President Obama's vow to confront Iran's dangerous and illicit acts."

He urged Obama to "aggressively enforce all sanctions against Iran's missile programs, support for terrorism and human rights abuses. No more looking the other way."

Washington imposed sanctions against businesses and individuals in January over another missile test in October 2015. But the IRGC said it would not bow to pressure.

"The more sanctions and pressure our enemies apply ... the more we will develop our missile program," Hajizadeh said on state television.

The IRGC maintains dozens of short and medium-range ballistic missiles, the largest stock in the Middle East. It says they are solely for defensive use with conventional, non-nuclear warheads.

Tehran has denied U.S. accusations of acting "provocatively," citing the long history of U.S. interventions in the Middle East and its own right to self-defence.