BERLIN (AP) _ Prosecutors have asked for 13- and 14-year sentences against two Palestinians accused in a West Berlin bomb attack that the state claims involved agents of the Syrian Government.

Prosecutor Detlev Mehlis urged the court Monday to impose the sentences to keep West Berlin from becoming ''a battleground for the Middle East.''

In his closing statement, he said testimony proved Syrian officials were behind the March 29 bomb attack on West Berlin's German-Arab Friendship Society that wounded nine people.

But he added ''it is not clear which level of Syrian authorities were involved'' in the plot.

Western governments have been monitoring the trial for evidence of Syrian involvement in international terrorist activities.

Federal government officials said earlier the trial's outcome would play an important role in West German-Syrian relations.

The judges were expected to deliver their verdicts Wednesday.

In their summations, the prosecutors said the bomb attack was plotted by Jordanian Nezar Hindawi, who was convicted in London last month of plotting to place a bomb aboard a jetliner of Israel's El Al airline.

They said Syrian officials provided explosives and helped Hindawi plot the West Berlin bombing allegedly carried out by the defendants, Ahmed Nawar Hasi and Farouk Salameh. The prosecutors asked for a 14-year sentence for Hasi and 13 years in prison for Salameh.

Mehlis told the court that testimony ''made clear the role of the fanatic Hindawi and his Syrian backers.''

''All those who believe they can commit crimes such as these must be shown that our society will not tolerate it,'' Mehlis said.''Tough sentences are a weapon in the struggle against terrorism. Mild sentences will only lead to further terrorist activity.''

Both defendants, under questioning by judges, acknowledged carrying out the bomb plot. The maximum punishment for the charges against them is 15 years in jail.

Defense attorneys pleaded for light sentences, saying their clients were politically naive and blamed the attack on Hindawi, Hasi's brother.

''We should make clear that neither of these two are professional terrorists,'' Hasi's attorney, Gisela Kihn, told the court. He said they were influenced by Hindawi.

Prosecutor Joachim Lawatsch, summing up his case, said testimony proved Hindawi traveled to Tripoli, Libya, in July 1985 to seek backing for a terrorist group he wanted to build in Europe.

When he failed to win Libyan support, Hindawi traveled to Syria with Salameh in January, Lawatsch said.

In pre-trial statements read into the court record, Hasi said he picked up the explosives used in the attack in West Berlin at the Syrian Embassy in East Berlin.