A new US intelligence report says the Kremlin spent $300 million since 2014 to try and influence several European countries using front companies and think tanks.

Russia has covertly spent more than $300 million in recent years trying to influence politicians and other officials in more than two dozen countries, including Europe.

According to the US State Department, a new American intelligence assessment of Russia's global covert efforts to support policies and parties sympathetic to Moscow targeted elections in Albania, Bosnia and Montenegro, among other countries, including Ukraine.

Some of the tactics Russia allegedly used included using front organisations to funnel money to preferred causes or politicians, including think tanks in Europe.

Putin was spending huge sums “in an attempt to manipulate democracies from the inside,” said a US official who spoke to reporters on condition of anonymity.

State Department spokesman Ned Price called Russia's covert funding an “assault on sovereignty.”

“It is an effort to chip away at the ability of people around the world to choose the governments that they see best fit to represent them, to represent their interests, and to represent their values,” he added.

American diplomats have been tasked with talking to the governments of some of the countries allegedly targeted by the Kremlin for malign influence operations, and although no information has been given about any politicians or parties who specifically benefited from Russian funding, classified information has been given to some specific countries, the State Department said.

The US also has a long history of covertly funding political groups and individual politicians, and been responsible for efforts to topple or undermine foreign governments, including democracies.