Senior intelligence officials in the United States and the United Kingdom had text conversations about 'our strange situation' as the FBI launched its investigation into whether Donald Trump's presidential campaign was colluding with Russia.

Text messages between then-FBI deputy director Andrew McCabe and his counterpart in Britain's MI5, Jeremy Fleming, were brought to light by the Guardian on Tuesday.

The correspondence raises questions about the UK's role in the early stages of the Russia probe amid heightened tensions between the American and British officials.

Earlier this month the countries became embroiled in a full-scale diplomatic spat after the leak of cables in which British ambassador to the US Sir Kim Darroch called Trump 'inept' .

The texts were revealed as the Justice Department is examining what led up to the launch of the FBI investigation.

FBI deputy director Andrew McCabe (left) and his counterpart in Britain's MI5, Jeremy Fleming (right), had text conversations about 'our strange situation' as the FBI launched its investigation into whether Donald Trump's presidential campaign was colluding with Russia

They are believed to be paying particularly close attention to the influence of another senior British intelligence official, Christopher Steele.

Steele, a former senior official at the UK's foreign intelligence agency MI6, compiled the infamous 'dirty dossier' in 2017, which alleged that Moscow attempted to interfere in the 2016 US presidential election and that there was potential collusion between Russia and Trump's campaign, along with other unverified and salacious claims about the president, including that he was vulnerable to blackmail from the Russians.

The dossier was paid for ultimately by Hillary Clinton's campaign. Many of the key claims were never verified.

The texts were revealed as the Justice Department is examining what led up to the launch of the FBI investigation. They are believed to be paying particularly close attention to the influence of another senior British intelligence official, Christopher Steele (pictured)

The most striking message was one from August 2016, three months before election day, in which Fleming noted that members of the FBI and MI5 had 'met on our strange situation'.

A source told the Guardian that the comment was in reference to discussions about Russian activities.

Senior FBI official Peter Strzok had traveled to London that same month to meet with Australian diplomat Alexander Downer. Downer agreed to speak with the FBI about Trump campaign adviser George Papadopoulos, who had told him that Russia had dirt on Democratic nominee Hillary Clinton.

McCabe and Fleming reportedly began texting with some regularity after the UK's Brexit referendum in June 2016.

The correspondence raises questions about the UK's role in the early stages of the Russia probe into their involvement in the 2016 election that elected Trump (pictured)

The source said many officials within the FBI regarded the vote as a sign that Russia's attempts to influence western elections may have been successful.

While the texts were cryptic and did not contain specific or sensitive materials, their regularity warrants intrigue.

US and UK intelligence agencies typically share information, but using texts as a mode of communication is atypical.

The role foreign governments played in the FBI's decision to launch an investigation remains a sensitive issue in the US months after the probe concluded.

In 2017 reports emerged that UK spy agencies played a pivotal role in alerting FBI officials to contacts between Trump's campaign team and Russian operatives.

The FBI opened its covert counterintelligence investigation, dubbed 'Crossfire Hurricane', into possible collusion between the Trump campaign and Russia on July 31, 2016.

Special counsel Robert Mueller eventually stepped in to take over the two-year probe, which did not establish a criminal conspiracy but did find multiple incidents in which Trump attempted to obstruct justice in the investigation.