Washington (CNN) Secretary of State Mike Pompeo decided not to include Saudi Arabia on the State Department's list of countries that recruit child soldiers and overruled his own team of experts, who argued that there was sufficient evidence to do so, a source familiar with the issue told CNN.

While the State Department is legally required to list all countries that use child soldiers, discussions about whether to include Saudi Arabia in the soon-to-be released report sparked a fierce internal debate between State Department officials and in-house experts.

Reuters was first to report the disagreement and Pompeo's decision to leave Saudi Arabia off the list.

A source familiar with the internal discussions told CNN that the State Department's experts on human trafficking recommended that the department include Saudi Arabia, in part, due to reports that the kingdom was using child soldiers from Sudan to fight for the US-backed coalition in Yemen -- a claim they said was corroborated by a military source.

Yet despite acknowledging that there are child soldiers fighting in Yemen, some State Department officials claimed that the evidence fell short of proving they were being led by Saudi commanders and pushed back on the experts' recommendation to include the kingdom on the list.

The source conceded that the decision was a very close call, adding that one could indeed argue there was not sufficient evidence, but the office that handles this issue felt there was enough to support its recommendation.

The State Department responded with only a brief statement to CNN: "The United States condemns the unlawful recruitment and use of child soldiers. We place great importance on ending the practice."

Saudi policy under scrutiny

News of the heated disagreement comes as Congress continues to question the Trump administration's policy on Saudi Arabia.

Despite bipartisan criticism over the kingdom's war in Yemen and its role in the killing of journalist Jamal Khashoggi , the White House has sought an even closer relationship with the Saudis, as is evident by its push to sell them billions of dollars in weapons and munitions despite opposition in Congress.

Those concerns have only been amplified by the Trump administration's recent push to counter Iran and its view of Saudi Arabia as a key player in that effort.

On Wednesday, Rep. Tom Malinowski, a Democrat from New Jersey, accused Pompeo of intentionally misleading the public about Saudi Arabia's use of child soldiers in Yemen.

"Once again, Secretary Pompeo has shown he'll go to any lengths to lie for the Saudi government," Malinowski said in a tweet linking to the original Reuters report.

"The Child Soldiers Prevention Act sets up a two step process for identifying and holding accountable governments that use children as soldiers. The first step is a simple factual determination: the State Department must issue a list of countries that do this," Malinowski said.

"This is all Pompeo had to do: acknowledge the fact that Saudi Arabia is using at least one child soldier in the war in Yemen. And this fact is impossible to deny," he added, pointing to a New York Times story from December 2018 about how Saudi Arabia uses Sudanese militias that recruit children to fight in Yemen.

Malinowski then argued that Pompeo could have included Saudi Arabia on the list but opted not to punish the kingdom with sanctions -- a decision he says he would have opposed but would have been more honest.

"In step 2 of the process, the State Department decides whether a country is making a sincere effort to stop using child soldiers, and, until then, what consequences (like sanctions) should be applied," Malinowski tweeted.

"Pompeo could easily have done the honest thing and listed Saudi Arabia as having child soldiers, and then decided not to punish it. I would have disagreed with that decision, but it would have been lawful. Instead, he told a blatant, and utterly unnecessary lie: that the children fighting for Saudi Arabia in Yemen have nothing to do with Saudi Arabia. This is another blow to the credibility of the State Department at a time when it desperately needs it, given the crisis with Iran," he added.

Such cases, though, can be hard to prove.

Tillerson faced similar criticism

President Donald Trump's previous secretary of state, Rex Tillerson, faced similar criticism when he declined in 2017 to add Myanmar, Iraq and Afghanistan to the list of countries using child soldiers, also doing so against the recommendation of multiple State Department experts, serving in various bureaus.

That decision prompted a group of State employees to pen a memo accusing department leadership of violating US law by refusing to call out these countries.

The employees wrote, "Beyond contravening U.S. law, this decision risks marring the credibility of a broad range of State Department reports and analysis and has weakened one of the U.S. government's primary diplomatic tools to deter governmental armed forces and government-supported armed groups from recruiting and using children in combat and support roles around the world."

At the time, then-State Department spokesperson Heather Nauert said some of the allegations involved only "one or two" child soldiers, though she agreed that reporters were fair to ask whether one or two was still too many.

She commented in a statement that Tillerson had "made this decision after considering the credibility of all of the information available to him from multiple sources."

Asked by CNN what message that sends -- a secretary of state ruling against his own experts' credibility -- Nauert replied, "I think it says that people had a different opinion on this particular matter, and the secretary weighed that opinion and thought about it."