WARSAW, Poland (AP) — Poland’s prime minister says he has information indicating that there is a growing threat of a “direct intervention” by Russia in Ukraine.

Donald Tusk said Wednesday that his assessment is based on information he has been receiving for the past dozen hours or so. He did not elaborate.

Tusk says “the threat of a direct intervention by Russia into Ukraine is greater than it was a few days or a couple of weeks ago.”

Poland’s Foreign Minister Radek Sikorski had expressed concern Tuesday night that a renewed build-up of Russian forces near Ukraine’s border heightened the risk of an invasion.

Sikorski said, “You do such things either to exert pressure or to enter.”

His comments appeared to contribute to a fall of financial markers Tuesday on Wall Street.

Copyright 2014 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.