Russia has declared it's no longer considers itself bound by a self-imposed moratorium on deploying nuclear-capable intermediate range missiles, a warning that potentially sets the stage for a new arms race as tensions between Moscow and Washington rise again over Ukraine.

MOSCOW (Reuters) -Russian former President Dmitry Medvedev blamed NATO countries on Monday for the abandonment of a moratorium on short- and medium-range nuclear missiles and said Moscow would take further steps in response.

Dmitry Medvedev, the former Russian president, has engaged in a heated social media exchange with Donald Trump, prompting the latter to announce the repositioning of U.S. nuclear submarines. Medvedev's recent aggressive rhetoric and warnings of nuclear conflict have drawn criticism and sparked direct responses from Western leaders,