Defense Secretary Jim Mattis on Thursday accused Iran of funneling money into Iraq to sway the outcome of its elections, calling it part of a broader pattern of destabilizing Iranian actions across the Middle East.

Mattis declined to say what outcome Iran is aiming for by allegedly interfering in Iraq, but he said Tehran is sending "not an insignificant amount of money" there to sway votes. He mentioned no dollar amounts.

Iran is widely seen as gaining more influence in Iraq during its period of instability following the takeover of much of northern and western Iraq by Islamic State militants in 2014. The IS militants have since been largely defeated, but Iraqi political stability still hangs in the balance.

"We have worrisome evidence that Iran is trying to influence — using money — the Iraqi elections," Mattis told reporters flying with him to Washington from the Persian Gulf island state of Bahrain, where he discussed Iran and other issues with senior government officials.

"That money is being used," he said, "to sway candidates, to sway votes — not an insignificant amount of money, we believe, and it's highly unhelpful."

"We know that they are doing what they can to impact the elections, and we don't like it."

Iran's political influence in Iraq has grown since the U.S. invaded to remove President Saddam Hussein in 2003, marking the start of a prolonged period of sectarian division, extremist violence and political strife.

The U.S. still has more than 5,000 troops in Iraq supporting its fight against remaining pockets of IS resistance. Iranian-backed Shiite militia groups also have fought IS, sometimes in coordination with Baghdad and sometimes not.

Mattis sharply criticized what he termed Iranian meddling elsewhere in the Middle East. He said Tehran is providing ammunition and explosives to fighters in Syria, and supporting rebels in Yemen.

He said the strait between the Red Sea and the Arabian Sea, off the coast of southern Yemen, is being used as a "proving ground" for advanced Iranian weaponry. This includes anti-ship missiles, radars, mines, ballistic missiles and explosive boats, he said.

On the other hand, Iran has stopped conducting what the U.S. calls provocative and dangerous maneuvers against U.S. Navy ships in the Persian Gulf, Mattis said.

"It's like an outlier, and I don't know why," he said. "They don't seem to be engaging in the same provocative behavior" in the Gulf as they were prior to last summer.

Navy Cmdr. William Urban said earlier Thursday that there have been no "unsafe and unprofessional" actions by Iranian naval forces in the Gulf since August 2017. Urban is a spokesman for U.S. Naval Forces Central Command in Manama, Bahrain.

Prior to that, Iranian vessels had periodically made high-speed approaches to U.S. ships that were considered dangerous provocations.

"It seems like they've absolutely made a conscious decision to give us more space," Urban said. "That is definitely a change in their behavior."

The last tense encounter between the U.S. Navy and Iranian forces in the Persian Gulf was recorded on Aug. 14, 2017, when an unarmed Iranian drone shadowed the USS Nimitz aircraft carrier at night and came close enough to F-18 fighter jets to put the lives of American pilots at risk, the Navy said at the time.

The drone did not respond to repeated radio calls and came within 1,000 feet (300 meters) of U.S. fighters. In a similar encounter Aug. 8, the Navy said an Iranian drone came within 100 feet (30 meters) of an F-18 preparing to land on the Nimitz.

For the first eight months of 2017, the Navy recorded 14 instances of what it describes as "unsafe and/or unprofessional" interactions with Iranian forces. It recorded 35 in 2016 and 23 in 2015.

The incidents at sea almost always involved the Revolutionary Guard, a paramilitary force that reports only to Supreme Leader Ayatollah Ali Khamenei. Some analysts believe the incidents are meant in part to squeeze moderate President Hassan Rouhani's administration after the 2015 nuclear deal.

Of the incidents at sea last year, the worst involved Iranian forces capturing and holding overnight 10 U.S. sailors who strayed into the Islamic Republic's territorial waters.

Iranian forces in turn accuse the U.S. Navy of unprofessional behavior, especially in the Strait of Hormuz, the mouth of the Persian Gulf, through which a third of all oil traded by sea passes.


Associated Press writer Jon Gambrell in Dubai, United Arab Emirates, contributed to this report.