If the unit quietly closes it will be a blow to Alex Aiken, executive director of the Government Communication Service.
Only last month Aiken paid tribute to the progress made by the unit, which sits under the GCS within the Cabinet Office.
An important component of its work is dealing with disinformation – which is also a core task of the national security communications team.
And while the latter comprises 10 civil servants, the rapid response unit has just five staff dedicated to it.
There is no mention of the rapid response unit in the national security capability review, published earlier this year, which made it clear that the comms priority was to expand the national security comms team.
PRWeek has established that the unit is funded only until October and that its future remains undecided. Officials plan to draw up options for its continued operation in due course.
The level of investment in the small unit stands in stark contrast to Aiken’s claim earlier this year that "Hostile states such as Russia reportedly spend between $600m and $1bn annually in sophisticated disinformation campaigns."
Doubt over the unit's continued funding has drawn criticism.
A former senior government comms director told PRWeek: "It seems absurd to attempt this for just six months and then abandon it. At a time when social media is spreading fake news at a faster and faster rate, government really needs to have this capability. There should be funding on an ongoing basis and it should be a priority."
Jon Trickett MP, shadow minister for the Cabinet Office, said: "With only six months of funding, the public could draw the conclusion that the Prime Minister’s fake news unit was just a PR exercise rather than a serious policy initiative."
Cabinet Office minister Chloe Smith MP has described how the unit "monitors news and information being shared and engaged with online, including misinformation and disinformation. It identifies emerging issues and ways to collaborate across Whitehall to respond quickly, accurately and with integrity."
She pledged in June: "We will be publishing blogs on the GCS website, outlining the progress of the unit."
Since then there has been just one blog post, last month, in which Aiken introduced the work of the unit. An example of its activities was its response to stories in April about murder rates in London overtaking those of New York for the first time.
He commented: "Action needed to be taken to prevent panic and provide reassurance in the face of these alarmist news stories. The unit activated social media content which helped to rebalance the narrative and reassure those who were most engaged with the topic."
A Cabinet Office spokesperson told PRWeek that "options for [the RRU's] continued operation will be drawn up in due course".
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