President Donald Trump took to Twitter on Sunday morning to attack special counsel Robert Mueller's investigation into Russian meddling in the 2016 election, reiterating his claim that it is a "Witch Hunt".

Trump's most recent remarks about the Russia probe come as the special counsel's investigation enters its second year.

President Donald Trump took to Twitter on Sunday morning to attack the special counsel Robert Mueller's investigation into Russian meddling in the 2016 election, reiterating his claim that it is a "Witch Hunt".

Trump started his tirade by criticizing a story reported by The New York Times on Saturday that his son, Donald Trump Jr., and other campaign aides met with a gulf emissary who offered help for the 2016 presidential election.

The man who reportedly met with Trump Jr. and campaign aides three months before the 2016 presidential election was the first sign that a country other than Russia offered to help the Trump campaign. Foreign governments or individuals getting involved in US elections is illegal.

The man, identified as Lebanese-American businessman George Nader, served as an emissary for the crown princes of Saudi Arabia and the UAE.

Erik Prince, founder of the security contractor originally known as Blackwater, arranged the meeting, during which Nader expressed the princes' desire to help Trump win the election, according to The Times.

The meeting also included an Israeli social media strategist, Joel Zamel, who reportedly proposed waging a large social media manipulation campaign in favor of the Trump team.

Trump continued his tirade by attacking the Russia probe as a "Witch Hunt" and wondering when the investigation will conclude. Trump then suggested that the special counsel should instead look into former presidential candidate Hillary Clinton's campaign, her use of a private email server, and the so-called Steele dossier.

Trump's most recent remarks about the Russia probe come as the special counsel's investigation unraveling Russia's interference in the 2016 US election enters its second year. It also resembles the shifting strategy of Trump's legal team from cooperating to adversarial with Mueller's investigation.

In the last few days, Trump's anger with the special counsel's investigation has been fueled by his claim that the FBI planted or recruited an informant in his campaign. After the president tweeted that accusation without evidence, his new attorney Rudy Giuliani told CNN: "I don't know for sure, nor does the president, if there really was one."

Trump continued his tweetstorm by saying that the special counsel's investigation will continue through the midterm elections this fall in order to hurt Republican candidates.

The president concluded his series of tweets on Sunday morning by criticizing Tony Podesta, the brother of former Clinton campaign head John Podesta. The former Podesta's lobbying work and firm have come under scrutiny from Mueller's investigation.

Read all of Trump's Sunday morning tweets: