Donald Trump returned to the US this weekend and resumed his crusade against the 'fake news media' which he has now accused of making up sources and fabricating stories about his administration.

Hot off the heels of a successful first foreign overseas tour, the president took to Twitter on Sunday to share his latest grievances with the press.

'It is my opinion that many of the leaks coming out of the White House are fabricated lies made up by the #fakenews media.

'Whenever you see the words 'sources say' in the fake news media, and they don't mention names it is very possible that those sources don't exist but are made up by fake news writers. #Fakenews is the enemy!' he said.

He then chastised the source of a leak who provided information about Manchester suicide bomber Salman Abedi to the press, a move which outraged UK officials.

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President Trump revived his crusade against what he calls the 'fake news media' on Sunday, sharing a string of tweets in which he accused journalists of making up sources and stories

'British Prime Minister May was very angry that the info the U.K. gave to U.S. about Manchester was leaked. Gave me full details!' he said.

The message comes amid reports, citing anonymous sources in the administration or close to it, that the president's son-in-law Jared Kushner tried to establish a back channel to communicate with Russian officials before the inauguration to avoid having their conversations monitored by US authorities.

The Washington Post was the first to report on it on Friday and cited 'insiders' who revealed that the Russian ambassador made note of Kushner's proposal in documents.

The back-channel claim falls into a wider pool of accusations about the administration's possible ties with Russian officials.

They have plagued the White House for months and are the subject of multiple ongoing congressional committee investigations.

Kushner has become the focus of the investigations in the past week, say more anonymous insiders.

The president's tweets came amid claims his son-in-law Jared Kushner (pictured right on Friday) tried to establish a back channel with Russian officials in December

White House sources said Kushner wanted to set up the channel to allow former National Security Adviser General Michael Flynn to communicate with Russian counterparts without being monitored by US authorities

The back channel proposal was reportedly dropped when Secretary of State Rex Tillerson was sworn in on February 1. The purpose of it had been to discuss Russia and the US's strategy in Syria.

The White House has acknowledged the meeting where it was reportedly discussed but said it was a courtesy get-together.

Trump maintains that no one in either his campaign or transition team colluded with Russian officials and the Kremlin has also dismissed the back channel claims.

Trump aides insisted over the weekend that the topic never came up during the G7 summit in Sicily, despite televisions playing round-the-clock coverage of the claims.

They insisted that the president was not asked about the reports by other foreign leaders and then refused to discuss it with a pool of reporters.

'We're not going to comment on Jared. We're just not going to comment,' said Gary Cohn, the president's chief economic adviser, during a press conference in Taormina on Saturday.

Kushner and Ivanka joined the president for the first part of his foreign trip last week. He is pictured with his wife at the Vatican last Wednesday

The New York Times reported that the White House plans to bolster its legal team with new attorneys in light of the accusations against Kushner.

Kushner spent the first half of the president's overseas trip by his side. He and Ivanka joined the president and first lady in Saudi Arabia, Israel and Rome but jetted back to Washington DC on Thursday.

Trump went on with his wife to Brussels and then Sicily for the G7 summit.

As he tweeted on Sunday, the president also criticized the media's coverage of the Montana special election.

Republican candidate Greg Gianforte won the race despite being cited for misdemeanor assault the day before polls opened for 'body-slamming' a Guardian journalist.

Trump said on Sunday: 'Big win in Montana for Republicans! Does anyone notice how the Montana Congressional race was such a big deal to Dems & Fake News until the Republican won? V was poorly covered,' referring to Gianforte's win.