The Soviet Union in effect shrugged off the latest US proposals on curbing medium-range nuclear missiles as ''lopsided.'' The Soviet position was conveyed Tuesday by Soviet Foreign Minister Andrei Gromyko during a visit here by his Czechoslovak counterpart.
Mr. Gromyko was quoted as saying, ''Why do the USA and its NATO allies keep . . . putting forward lopsided proposals, patently unacceptable to the other side? This can mean only they intend to continue to block the negotiations and evade agreement.''
The official news agency Tass used unusually acid language to denounce Reagan's speech and ignored his call for peace.