Facebook has claimed that only three Kremlin-linked accounts were found to have bought advertisements which could have influenced the Brexit referendum.
These accounts, which Facebook claimed are associated with a Moscow-based organisation called the Internet Research Agency (IRA), spent $0.97 (72p) on advertisements.
In a letter to the Electorial Commission, Facebook said the adverts were loaded by users' web browsers only 200 times over a four-day period in May 2016.
They were targeted to US audiences and "concerned immigration, not the EU referendum", the social media firm added.
As well as being quizzed on any attempts at foreign meddling in the referendum, Facebook is being investigated by a committee of MPs over the impact of "fake news" being circulated on social media.
Conservative MP Damian Collins told CEO Mark Zuckerberg the Digital, Culture, Media and Sport Committee would attempt to uncover "the role of foreign actors abusing platforms such as yours to interfere in the political discourse of other nations".
Facebook previously claimed as many as 126 million Americans – around half of the US population of voting age – may have seen around 80,000 posts that were published by the IRA.
The company did not respond to enquiries from Sky News about the methodology it used to identify IRA accounts, nor whether the advertising campaigns it notified the Electoral Commission about were the same ones it had identified to the US House Intelligence Committee.
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