President Donald Trump on Tuesday blasted former campaign adviser George Papadopoulos as a "liar" and "low level volunteer" after it was revealed a day earlier that he had secretly pleaded guilty and struck a cooperation agreement with special counsel Robert Mueller.

"The Fake News is working overtime. As Paul Manafort lawyer said, there was 'no collusion' and events mentioned took place long before he.......came to the campaign. Few people knew the young, low-level volunteer named George, who has already proven to be a liar. Check the DEMS!" Trump tweeted in a pair of tweets Tuesday morning.

Even with the guilty plea and two indictments, the president insisted the "biggest story" on Monday was the resignation of Tony Podesta from his lobbying firm. NBC News has reported Podesta and the Podesta Group, which received payments from Manafort, are among the subjects of Mueller's investigation.

Trump followed up with one more post about tax cuts.

"I hope people will start to focus on our Massive Tax Cuts for Business (jobs) and the Middle Class (in addition to Democrat corruption)!" he wrote.

The posts were Trump’s second Twitter screed since Mueller's office announced Monday that Papadopoulos had secretly pleaded guilty three weeks ago to lying to federal agents about his contacts with Kremlin-connected Russians.

Papadopoulos, 30, spent 11 months on the Trump campaign as a volunteer foreign policy adviser after working for Ben Carson's campaign.

Trump followed up with one more post about tax cuts.

"I hope people will start to focus on our Massive Tax Cuts for Business (jobs) and the Middle Class (in addition to Democrat corruption)!" he wrote.

The posts were Trump’s second Twitter screed since Mueller's office announced Monday that Papadopoulos had secretly pleaded guilty three weeks ago to lying to federal agents about his contacts with Kremlin-connected Russians.

Papadopoulos, 30, spent 11 months on the Trump campaign as a volunteer foreign policy adviser after working for Ben Carson's campaign.