According to Gosar, last month the State Department responded to his inquiry from September requesting information about whether US aid was benefitting neo-Nazi Azov's in Ukraine.
Gosar raised his concerns this week in a letter addressed to US Secretary of State Antony Blinken.
"Of major concern is the part of the State Department letter that alleges the Azov Battalion disbanded but was later established as the Special Purpose Azov Regiment under the National Guard of Ukraine," Gosar said in the letter obtained by Sputnik.
"Just because the Azov Battalion morphed into the Azov Special Purposes Regiment and became part of the NGU does not mean that the group is no longer a neo-Nazi organization."
Although the Azov Battalion went through a name change in 2015, evidence remains clear that Azov is still a "vicious" neo-Nazi group, according to Gosar.
"The US should not provide any assistance to Azov, anything less than this is morally reprehensible," Gosar said in the letter to Blinken.
"The US should also not make a fool of itself and allow neo-Nazis to circumvent the law through name changes and incorporation under the authoritarian Kiev regime's armed forces."
Gosar said he found it more concerning that the State Department, in its response to his inquiry on the Azov, claimed it sees no evidence that the Azov Regiment, Ukraine's National Guard, or any Ukrainian armed forces systemically promote neo-Nazi ideology or use Nazi symbology.
"Because there is overwhelming evidence to the contrary, this statement at best reflects poorly on the competency of the State Department and its ethics," Gosar said.
Gosar called on Blinken and his team to be replaced if they are unaware about Nazi affiliations in Ukraine.
The US lawmaker has called for the State Department, after reading his response, to clarify whether it still determines there are no Nazis affiliations in Ukraine and to clarify whether any US aid has gone to Azov groups.
*banned as an extremist group in Russia