Minority Leader Chuck Schumer called for an independent criminal investigation and possible prosecution of ex-national security adviser Mike Flynn who was forced to resign over his discussions with the Russian ambassador before President Trump took office.

The New York Democrat also pressed Attorney General Jeff Sessions to recuse himself from any Justice Department action, citing DOJ regulations that prohibit individuals with political or personal ties to the subject of the investigation from leading the probe.

"Gen. Flynn's resignation is not the end of the story. It is merely the beginning," Schumer told reporters Tuesday afternoon. "His resignation raises more questions than it answers and the American people deserve to know the truth."

Schumer didn't say whether the Justice Department should launch a probe or whether there should be an independent prosecutor called in to lead one. But he was adamant that the questions surrounding Flynn's ties to Russia "must be asked by independent and unbiased law enforcement officers."

"They must be answered truthfully by administration officials and any attempt to lie or mislead must be countered with the full force of the law," he said.

In addition, he said, all administration officials, including the president himself – "from those sitting in cramped cubicles to the man occupying the Oval Office" — should face questions about contacts between the Trump campaign and his administration with Russia, he said.

"What were the extent of the [Flynn's] conversations and contacts with Russia?" Schumer asked. "Who else from the administration or the campaign had contact with the Russians … and why wasn't Gen. Flynn fired" when Trump administration officials discovered he had not been truthful about his Russian contacts to the president and the vice president?

"Why did they act only when they were caught misleading the media?" he added.

Schumer also insisted that Sessions cannot lead any probe under DOJ rules. The Alabama Republican, he recalled, served as chairman of Trump's national security advisory committee alongside Gen. Flynn.

"Because the rules are so clear, I expect Jeff Sessions to recuse himself" to ensure that the probe is independent.

"The American people deserve a full investigation and we need an impartial investigation," he said.