Measured Soviet response to MX

In keeping with the early tack by the new Soviet party leader, Yuri V. Andropov, on relations with Washington, the Communist Party newspaper Pravda issued a firm but relatively polite rejoinder to Reagan administration plans to deploy the MX missile.

Monitor correspondent Ned Temko reports that a lengthy Pravda commentary accused Mr. Reagan of endorsing a plan that violates the SALT II strategic arms treaty by envisaging construction of new missile silos.

Diplomats note that the article made only brief reference to the alleged SALT violation, and that even this was buried deep in the article - although it is possible further statements will follow up on the charge.

Pravda also offered hedging support for Mr. Reagan's parallel call for new ''confidence-building measures'' such as expanded exchange of information on weapons tests. The gist of the Pravda argument was that such proposals were ''useful'' but should be pursued only as part of further genuine arms-control accords, rather than as a substitute for them.

Since becoming Soviet party leader Nov. 12, Mr. Andropov has ruled out ''preliminary concessions'' in any US-Soviet thaw; has stuck to stated Soviet policy on issues in dispute; but has signaled apparent readiness to meet the Americans halfway on at least an atmospheric improvement in relations.

In that context, diplomats noted the absence in the Pravda article of the kind of charged rhetoric that had come to mark Soviet statements amid heightened superpower tension in the final weeks of Leonid Brezhnev's tenure as party leader.