The Kremlin yesterday accused Peking of trying to force a "unilateral withdrawal" of Soviets troops that would leave the disputed Soviet-Chinese border open to Chinese invasion along "a front stretching for thousands of kilometers."

The apocalyptic scenario was contained in an editorial in Pravda, the official Communist Party newspaper, that appeared to supply remarkable details to the complex dealings between the two countries over the explosive issue of their joint border.

The editorial warned of the Chinese intentions and said that if the Soviet Union went along, "the Soviet population [in the border areas] would be left without any protection and coverage while Chinese troops would remain on the old frontier and Chinese authorities would be given the opportunity to 'develop' these areas."

Pravda's lengthy commentary comes at a time when the Soviets are busy demonstrating a tough response to what the press here has described as yet another Chinese rejection three weeks ago of a new Soviet attempt to improve relations. Soviet President Leonid Brezhnev has been traveling this week in Siberia with his Defense Minister Dmitri ustinov on a journey which Western experts here are certain will include inspections of Soviet border military installations.

[In Peking, the official New China News Agency called the Soviet Union "the most savage gendarme in the present-day world." The agency alluded to Brezhnev's current tour of Siberia and the Soviet Far East and criticized Soviet military presence in areas "which the Soviet Union claims as its own or had wrested from its neighboring countries."]

Rejection of the Soviets' February proposal to the Peking leadership for talks on the border dispute and other tensions between the two Communist powers" served as a kind of signal for a new wave in the anti-Soviet campaign in China which has never ceased for a number of years now," Pravda declared.

The Soviets said recently that the Chinese rejected their Russian neighbor's offers to talk after insisting on certain unspecified concessions by the Soviets. Yesterday's editorial spells out the Soviet version of what the Chinese are seeking.

The Chinese have long standing claim to thousands of square miles of territory north of the Amur River that was ceded by China in the 19th century to the expansionist and more powerful Czarist Russia. The Chinese also want the Soviets to acknowledge the "illegality" of these and other areas where more than 20 million Soviet citizens now live.

Declared Pravda, "Of course, no one maintains that the Soviet Union and China have no need for specifying the border in some areas as defined by the Russian-Chinese [Czarist era] treaty documents. It is not difficult to carry out this work: One must take the documents and carry out the necessary specifications on their basis." This is implicit rejection of the Chinese position.

According to Pravda, both countries agreed to a "status quo" in the border area. "We understand this [to be] preservation of the present border defined by the Russian-Chinese treaty documents," Pravda asserted. "Yet the Chinese link the status quo to the recognition of 'disputed areas' and recarving of the historically shaped-out border. Naturally, the Soviet Union cannot agree to such an interpretation."

The Chinese also demaned "withdrawal of Soviet troops from Mongolia and that they be pulled back all along the entire Soviet-Chinese border," according to the editorial. Western intelligence experts have estimated that at least 500,000 Soviet troops are along the border. After armed clashes along the Ussuri River, the countries in 1969 tried to arbitrate their differences through a joint commission, but the attempt has failed.

Pravda yesterday told how a 1964 effort to mediate the border dispute exchange maps of the areas and the Soviets discovered the Chinese had drawn new borders deep within Russian turf. "Behind the line which Soviet border guards have been protecting since the creation of the Soviet State."

For the Kremlin to recognize these areas as "disputed," said Pravda, would allow the Chinese to question the basic validity of the Czarist Russian acquistions, make it possible for Peking to argue there is no valid continuous boundary between the two nations and "claim considerable areas of Soviet territory before discussing the question of [A] border." Should those things take place, Pravda warned, then Peking could press for the "unilateral withdrawal" of Soviet troops and occupy the areas.

Kremlin in concern about its Chinese border is a deep, emotional issue. Western experts have written that the Soviets contemplated full scale war with China in 1969, and President Nixon's former aide H. R. Haldeman has made a similar asseration [denied by the Soviets]. In 1974, the Soviets began construction of a new rail line from the resourches-rich Siberian interior that is several hundred miles north of the existing Trans-Siberian Railroad, and thus more secure from interdiction.