Rob Goldman's tweet was retweeted by President Donald Trump.

His view contradicted special counsellor Robert Mueller's recent indictments, in which 13 Russians were charged with meddling in the election via social media and other means.

Mr Goldman is reported to have apologised to Facebook staff.

The BBC understands that his tweets were not the views of the company.

In a series of tweets, Mr Goldman said that Russia's misinformation activity had been designed to "divide America" but added that "the majority of the Russian ad spend [on Facebook] happened after the election".

However according to the indictment, the ads were only part of Russia's activity on the social-media platform.

In the document, Facebook is mentioned 35 times.

The 13 Russians are accused of setting up fake accounts using stolen US identities, setting up themed groups and promoting political rallies throughout 2016, using Facebook, Instagram, YouTube and Twitter.

In his most recent tweet at time of writing, Mr Goldman implied that the point he had been trying to make was that Russia's campaign of misinformation had continued since the election.

"If only one could edit one's tweet," he wrote.

According to Wired, he sent a message to staff that read: "I wanted to apologise for having tweeted my own view about Russian interference without having it reviewed by anyone internally.

"The tweets were my own personal view and not Facebook's. I conveyed my view poorly.

"The special counsel has far more information about what happened [than] I do - so seeming to contradict his statements was a serious mistake on my part."

Facebook said it would not comment on internal messages shared by employees but it did not question Mr Mueller's findings.