MOSCOW, JUNE 13 -- There are increasing signs here that a crucial battle over the controversial economic and political reforms proposed by Kremlin chief Mikhail Gorbachev is now gripping the Soviet leadership, with veiled attacks on Gorbachev's allies as well as his foes spilling into the Soviet media and into speeches being made around the country.

The verbal battle is unfolding in advance of a major Communist Party meeting and referendum on Gorbachev's calls for more radical economic reform measures expected later this month.

Some of Gorbachev's closest political allies are now falling into the line of fire, according to Soviet and western analysts here. Foreign Minister Eduard Shevardnadze and Moscow party boss Boris Yeltsin, for example, have been the subject of indirect attacks in the central Soviet media in recent days. They are the two members of the ruling Politburo most closely allied with Gorbachev.

At the same time, potential Politburo opponents to Gorbachev's proposals have also come under media attack, including three members of the ruling body's old guard which is thought to favor a slower course of reform than that espoused by Gorbachev. They are Gaidar Aliyev and Vladimir Shcherbitsky, named to the Politburo under former Kremlin leader Leonid Brezhnev, and Sergei Sokolov, who was removed two weeks ago as defense minister but is still a nonvoting Politburo member.

Gorbachev is expected to use a major plenary session of the powerful Communist Party Central Committee which is expected to be held in the next two weeks as the forum to broaden his economic reforms to what he describes as a more "radical" level. But it is still unclear how strongly he will be supported in the bid by the 307-member body or the 11-man Politburo at its helm.

One large unknown is what role second-ranking Politburo member Yegor Ligachev, considered by western analysts as alternately a foe and a supporter of some of Gorbachev's reforms, will play at this crucial juncture in the Soviet leader's 2 1/2-year-old reform movement.

As the party's chief ideologist, Ligachev is well positioned to support or oppose Gorbachev's reforms.

He apparently is facing a challenge to that role, however, from Alexander Yakovlev, a close Gorbachev ally and Central Committee secretary, who evidently has launched a campaign to take over the ideology portfolio from Ligachev.

Ligachev, known as the strongest force in the Soviet Communist Party next to Gorbachev, has raised his profile and added to the attention being paid to his position recently by criticizing Shevardnadze, one of Gorbachev's leading allies.

Last week the 66-year-old Ligachev flew to the Georgian capital of Tbilisi and publicly denounced corruption and bad management in the republic's Communist Party during the late 1970s and early '80s, the period when Shevardnadze served as Georgian party boss.

In his June 4 speech in Georgia, Ligachev blasted "flagrant violations" in some earlier agricultural practices, declines in Georgian industry since 1980 and the generally deplorable economic performance from 1976 to 1986.

Shevardnadze, believed to be one of the most fervent proponents of radical economic reform within the Kremlin leadership, was generally in command of the Georgian economy as first secretary of the republic between 1972 and 1985.

He was promoted to foreign minister and Politburo member two years ago in one of Gorbachev's first major personnel moves. Since Shevardnadze's July 1985 move to Moscow, many of his former key aides in Tbilisi have been ousted by his successor.

A running attack in the official Soviet media against the anti-Semitic, so-called historic preservation group Pamyat is also being interpreted by some western diplomats here as veiled criticism of Yeltsin, the Moscow party chief who is a candidate Politburo member closely aligned with Gorbachev. Yeltsin met with Pamyat members here a month ago.

Aliyev, who is among the potential Politburo opponents to Gorbachev's proposals, is indirectly criticized in a recent article in the official newspaper Socialist Industry. It railed against the economic shortcomings in Azerbaijan in the early 1980s, when Aliyev was party boss of the Central Asian republic.

The criticism, coupled with Aliyev's pointed absence from official Politburo gatherings in the past six weeks, have fueled speculation that he may come under even more severe scrutiny at the upcoming plenum.

Articles in the Communist Party newspaper Pravda and other journals have also criticized corruption in the Ukraine, where Shcherbitsky has been party boss for 15 years. A front-page article this week in Pravda referred to continuing purges in the Ukraine as well as Uzbekistan and Kazakhstan.

Although party bosses in both Uzbekistan and Kazakhstan have been ousted recently, Shcherbitsky is expected to retain his post.

Soviet media reports criticizing lax military standards are widely interpreted here as attacks on Sokolov's management of the Defense Ministry, which ended abruptly two weeks ago after a young West German pilot flagrantly violated Soviet air defenses and landed in Red Square.

Such public exposure of senior Soviet officials to criticism, however blunted, is unusual. Some analysts here say that it does not represent clashes within the Politburo so much as a broadening of the official policy of glasnost, to allow public criticism of political leaders who are in good standing as well as those earmarked for purging.

The open criticism in the media, along with the political maneuvering taking place before the plenary meeting, appear to signal a rallying of factions on issues extending all the way from possible economic reforms to party ideology.

The plenum may result in a turnover in the Politburo or other senior personnel changes, according to some Soviet officials and western diplomats based in the Soviet capital.

Sokolov is almost certain to lose his seat as nonvoting Politburo member, they say.

In the apparent positioning for power, the focus of attention is on Ligachev and Yakovlev.

Ligachev has used his position as senior party official in charge of ideology to take conservative stances on such crucial issues as the telling of Soviet history and the role of religion in contemporary Russia.

In the past six weeks Yakovlev, the Central Committee secretary in charge of propaganda and a nonvoting Politburo member, has devoted a major speech in the Central Asian city of Dushanbe and articles in the official publications Kommunist and Partivnaya Zhizn to the subject of ideology.

No real ideological conflicts have surfaced so far between Yakovlev and Ligachev, Soviet dissident historian Roy Medvedev said in an interview this week, "But the potential exists."