SAN FRANCISCO, April 17 (Reuters) - Microsoft said on Wednesday that Russian online campaigns to influence the upcoming U.S. presidential election kicked into gear over the past 45 days, but at a slower pace than in past elections.

Russia-linked accounts are disseminating divisive content aimed at U.S. audiences, including criticising American support of Ukraine in its war with Russia, researchers at the tech giant said in a report.

While the Russian activity Microsoft observed is not as intense as around the previous elections, it could increase in the coming months, the researchers said.

“Messaging regarding Ukraine - via traditional media and social media - picked up steam over the last two months with a mix of covert and overt campaigns from at least 70 Russia-affiliated activity sets we track,” Microsoft said.

The most prolific of such Russian campaigns is linked to Russia’s Presidential Administration, they added. Another one is aimed at posting disinformation online in various languages, with posts typically starting with an apparent whistleblower or citizen journalist posting content on a video channel. That content is then covered by a network of websites that include DC Weekly, Miami Chronical and The Intel Drop.