By
The US sanctions, announced on Friday, target officials and business people around President Vladimir Putin in an aggressive response to alleged Russian meddling in the 2016 US election. The sanctions have triggered steep falls in the rouble and some Russian stocks.
Speaking before Russia's lower house of parliament, Medvedev said the new sanctions were an attempt to capture global markets for US companies.
"Measures in response should be well thought-out, not inflict harm to ourselves, and be appropriate. I do not rule out that... we will have to weigh all aspects of our cooperation with the United States," Medvedev said.