Rome — The crackdown in Poland has driven the Italian Communist Party (PCI), the largest communist party outside the Soviet bloc, to issue its sharpest attack ever on the Soviet Union.
The attack took the Soviets to task for their interference in Poland and economic inefficiency. That the Italian Communists stopped short of making a definitive break with their Russian mentors indicates the criticism was largely tailored for home consumption.
Enrico Berlinguer, leader of the PCI and founder of Eurocommunism, this week repeated earlier statements that the situation in Poland is unacceptable.
''The Poles should be able to resolve their problems in independence and autonomy and not by means of force and repression,'' Berlinguer told the PCI's Central Committee, which met this week to discuss their position on Poland.
The differences between the Italian and Soviet communist parties on the Polish trade union movement Solidarity began a year ago, when the Soviets accused the Italians, in a private letter leaked to the press, of going to the aid of the enemies of socialism.
But a 17-page policy paper issued Dec. 30, ''Reflections on the Dramatic Events in Poland,'' strongly condemned the Soviet Union for being a great negative weight in the events in Poland.
This provoked Soviet ambassador to Italy, Nikolai Lunkov, to lash back publicly that the PCI's ''position and support of Solidarity had helped bring Poland to the brink of civil war.''
Many communists feared the Soviets would go even further by officially excommunicating the PCI, but that fear now appears more remote following Mr. Berlinguer's explicit statement Jan. 11 that ''we are not seeking a break (with Moscow), instead we are firm in demanding and safeguarding relations based on parity and autonomy.''
In addition, the PCI has undoubtedly mitigated Soviet wrath by its refusal to endorse the sanctions and actions proposed by the United States, the European Community, NATO, and even the Italian government. In his statement, Berlinguer even criticized the sanctions, pointing out that the dollar has gone up since President Reagan announced his sanctions.
However, the second theme of Berlinguer's criticism -- the public rejection of Soviet-style communism -- strikes at the very heart of Soviet ideology and may not be as easily overlooked by the Soviets.
The Italians say that because of its proven economic inefficiency and restriction of liberty, the Soviet model of communism is not repeatable or transferable to the West. ''Today in the Soviet Union and in countries of so-called socialism, there are signs of great decay,'' stated the position paper on Poland.
In its place, Berlinguer is promoting his idea of the ''terza fase,'' or third phase, which lies vaguely somewhere between communism and capitalism. The concept which relies principly on uniting the labor movements of the West is, at this point, murky at best.
Berlinguer's stand on Poland, Western diplomats believe, is calculated to cut his losses.
The Italian Communist Party, which is almost 2 million strong and controls 30 per cent of the vote, experienced a noticeable decrease in party memberships following the Soviet invasions of Afghanistan, Hungary, and Czechoslovakia.
''Berlinguer is trying to disassociate himself from an action that is deplored by most of the people in this country,'' said one analyst.
But Berlinguer's attack on the Soviet model has produced dissent from within the pro-Soviet ranks of his own party, which many estimate may be as much as 30 per cent of the rank and file.
The possibility of a split in the ranks of the Communist Party is also thought to be a tempering influence on the course Berlinguer will choose in the immediate future. Analysts here do not feel that the move away from the Soviet Union will coincide with an attempt to establish closer ties with other Western European countries or the United States.