New York: Some 10 million people in the United States saw politically divisive ads on Facebook that the company said were purchased in Russia in the months before and after last year's US presidential election, Facebook said on Monday.

Facebook, which had not previously given such an estimate, said in a statement that it used modelling to estimate how many people saw at least one of the 3000 ads. It also said that 44 per cent of the ads were seen before the November 2016 election and 56 per cent were seen afterward.

Photo shows a sign at Facebook headquarters in Menlo Park, California. Credit:AP

The ads have sparked anger toward Facebook and, within the United States, toward Russia since the world's largest social network disclosed their existence last month. Moscow has denied involvement with the ads.

Facebook has faced calls for increased US regulation from US authorities. Chief Executive Mark Zuckerberg has outlined steps that the company plans to take to deter governments from abusing the social media network.