BAGHDAD — Iraq, facing heavy pressure from the United States, has denied signing deals for weapons and ammunition with Iran in apparent violation of international sanctions.

Iraq’s Defense Ministry said a variety of international firms had sought to supply Iraq with ammunition and night vision equipment, including one company from Iran.

But contrary to media reports, “no contract was signed with the Iranian company,” the ministry said in a statement posted on its website on Tuesday.

Washington has piled pressure on Baghdad after reports that it had signed multiple deals for weapons, gear and ammunition emerged earlier this week.

State Department spokeswoman Jen Psaki said that “any transfer of arms from Iran to a third country is in direct violation” of United Nations sanctions on the Islamic republic.

“We are seeking clarification on this matter from the government of Iraq and to ensure that Iraqi officials understand the limits that international law places on arms trade with Iran,” she added.

America is by far the largest supplier of military equipment to Iraq, with Psaki saying the US has provided more than $15 billion in equipment, services and training.

The US has speeded up delivery of equipment including Hellfire missiles to Iraq to help Baghdad battle militants who seized one city near Baghdad and parts of another in January.

But officials have complained about the pace of delivery of some American weapons, providing an opening for other countries to make gains in diplomatic and military ties — a situation Baghdad could also seek to use as leverage with Washington.

Both the Russian and Chinese foreign ministers discussed arms sales during recent visits to Baghdad.