The diplomat who is in line to be America's next NATO ambassador said Monday that former National Security Advisor Susan Rice has been suspected 'for weeks' of involvement in an effort to publicly unmask Donald Trump associates whose names appeared in foreign intelligence reports.

And he claimed ten days ago that if Rice and her deputy Ben Rhodes were behind politically motivated leaks of classified intelligence, former president Barack Obama was also in the know.

'Former State Department colleagues of mine have been talking about Susan Rice's role for weeks,' Richard Grenell told DailyMail.com on Monday

'She and her team certainly were hyper-partisan throughout their tenure. It makes sense.'

Richard Grenell, the diplomat in line to be the Trump administration's NATO ambassador, said Monday that State Department insiders have discussed Susan Rice's role in an 'unmasking' scandal for weeks

Rice (center, last July) reportedly asked intelligence agencies dozens of times to show her the names of Trump-related campaign personnel that had been 'masked' from transcripts of foreign intelligence intercepts

Grenell did not disclose who his former colleagues are.

Rice is the Obama administration official whose name became a punchline after her repeated false claims that the 2012 Benghazi terror attacks were caused by a crude Internet video.

WHAT IS UNMASKING? When U.S. intelligence services conduct surveillance of foreign targets, it's possible that American citizens can be swept up in recorded conversations, intercepted emails or other surveillance. That can happen when Americans who are not targets of an investigation are 'incidentally' captured talking to a target. it can also occur when targets merely mention them during a conversation or in a document. When this happens, intelligence analysts routinely delete the Americans' names and replace them with vague identifiers like 'U.S. Person Number One' or 'Person A' – masking their identity from other government officials who may look at reports. Senior intelligence officials can request the 'unmasking' of those names under certain circumstances, but that creates a risk that the names will be leaked. Advertisement

From her position as chief of the National Security Council last year, according to a Bloomberg report, Rice asked government agencies to identify names that had been withheld from raw intelligence reports linked with Trump campaign and transition figures.

There is not necessarily anything illegal or unusual about a national security advisor seeking to unmask names in raw reports, in order to fully understand the meaning of intercepted conversations.

But leaking those names to people who lack the security clearance to view the source documents is a federal felony.

One such criminal leak involved Gen. Michael Flynn – Rice's short-lived successor – whose name was leaked to a reporter just days into the Trump administration.

Routine surveillance conducted on phone conversations of Russia's U.S. ambassador Sergey Kislyak revealed that he had been talking with Flynn.

Flynn was later forced out of office following reports that he had failed to acknowledge those conversations included talk of the potential for relaxing U.S. sanctions on Moscow.

The controversy reached public scandal level when a partial transcript of one call was leaked to a Washington Post columnist.

Rice had access to intelligence reports that also contained 'valuable political information on the Trump transition such as whom the Trump team was meeting, the views of Trump associates on foreign policy matters and plans for the incoming administration,' according to Bloomberg.

But she insisted last month that she was in the dark about any efforts to identify Trump-linked private individuals in intelligence reports, after House Intelligence Committee Chairman Devin Nunes publicly exposed the 'unmasking.'

'I know nothing about this,' Rice told PBS.

Grenell made the first prediction, back on March 24, that Rice would be embroiled in the unmasking fiasco, saying that then-president Barack Obama would also have to have known

Grenell fingered Rice and her deputy Ben Rhodes (right) as political operators inside the National Security Council, the most likely personnel to leak classified information in any plot to harm the Trump campaign

Grenell has served as a spokesman to four different U.S. Permanent Representatives to the United Nations, including Ambassador John Bolton's tenure under President George W. Bush.

He was also briefly Mitt Romney's national security spokesman while the former Massachusetts governor was running for president in 2012.

Grenell was the first to publicly raise Rice's name in conjunction with the unmasking of Americans' names during the final year of the Obama administration, along with that of Rhodes, the former Deputy National Security Advisor for Strategic Communications.

One 'unmasked' name has already been leaked to The Washington Post, that of disgraced Gen. Michael Flynn who succeeded Rice as National Security Advisor

'The Obama team is claiming that this is a safe legal issue because they were supposedly trying to listen to foreigners,' Grenell said during a March 24 Fox News Channel 'Hannity' broadcast.

'But within that realm there could have easily been a political calculation to listen in, and then to take those transcripts and the summaries of those transcripts, make sure that those in the NSC and the political people – like Ben Rhodes and Susan Rice – make sure that they have them so they can leak them to reporters.'

'I think that it would be easy to figure out if Susan Rice and Ben Rhodes knew about this,' he added, 'because if they did, clearly President Obama knew about it.'

'That's the political team inside the NSC. They would have been trying to help do something against Trump during the election. So I think let's just figure out if they knew, and we'll have something leading to a political scheme.'

Grenell said ten days ago on 'Hannity' that what started out as an 'unintentional sweep' which snagged Trump campaign personnel in an intelligence net ultimately morphed into 'intentional' leaks as Rice (right) and others weaponized U.S. intelligence for an election

Grenell said on 'Hannity' that what started out as an 'unintentional sweep' that snagged Trump campaign personnel in an intelligence net ultimately morphed into 'intentional' leaks.

He added that he had received intelligence briefings every day for eight years while he worked at the UN, and never once saw raw transcripts of phone intercepts.

White House Press Secretary Sean Spicer declined to pile on Susan Rice during his Monday afternoon press briefing.

'I'm not going to start going down that road,' he said.

Grenell's expected nomination to lead the U.S. NATO mission has appeared stalled for the past four weeks since the first word of it emerged.

But a White House aide said Monday that the administration is viewing it with a renewed sense of urgency in order to get him confirmed before a May 24-25 NATO summit in Brussels, Belgium.

President Donald Trump is expected to participate in that event on its second day.