PRAGUE (Reuters) - The Czech Republic wants to modify some parts of the European Union's proposed new trade measures against Russia, Prime Minister Bohuslav Sobotka said on Tuesday, warning that escalating sanctions was risky.

EU leaders decided at a summit on the weekend that direct engagement of Russian troops in the war in eastern and southern Ukraine called for a stepping up of sanctions imposed so far unless Russia pulled its soldiers back.

The European Commission is to prepare a final draft of new sanctions against Moscow over its involvement in Ukraine by Wednesday and EU governments will make a decision on the final shape of the package by Friday.

Russia denies sending troops or armor over the border.

The sanctions plan has divided EU leaders. Sobotka, following the weekend summit, reserved the right to object to new measures and questioned their effectiveness.

After receiving proposals from Brussels, he told Czech media on Tuesday the country would make unspecified suggestions on the proposals but also saw a wider problem with the EU's approach.

"Europe should not hurt itself by sanctions. I consider the escalation of sanctions to be a very risky thing," he said.

"The problem right now is not just in evaluating the Commission proposal, trying to modify it so that it hurts the Czech Republic and our national interests as little as possible," he added in comments broadcast on Czech Television.

"The problem is that if sanctions are escalated now, there will be a reaction from Russia and we are not able to estimate at this point what impact the next wave of sanctions by Russia against EU countries will have."

The Czech cabinet will discuss the proposed measures on Wednesday.

Slovak Prime Minister Robert Fico has called sanctions "meaningless and counter-productive" and threatened to veto any measures that harmed Slovakia's interests. Austria and Hungary are also skeptical.


(Reporting by Jason Hovet and Jan Lopatka; editing by Ralph Boulton)