Like reluctant suiters in an arranged marriage, the Palestine Liberation Organization and King Hussein of Jordan are being pressured to heal their bitter rupture by Arab powers anxious to form a united bargaining front for Mideast peace talks.

The ultimate aim to erase Israel's objections to going to the bargaining table with the Palestinians by either making them a part of a common Arab delegation of putting them under Jordan's wing.

While the first steps toward ending six years of rancor have been taken, neither side was willing to say in interviews here and in Beirut this week that the breach has been healed. Moreover, both Hussein and the PLO are playing Alphonse and Gaston over who should make the next move.

"We were ready. We went to Amman. Now it is King Hussein's turn," said Yasir Abdou Rabbou of the Popular Democratic Front for the Liberation of Palestine, a member of the PLO's ruling executive council.

Jordanian Information Minister Abu Odeh, insisted, however, "I think the PLO is in need of Jordan, not vice versa. So I expect the PLO to take another step."

Time is running out, though, since the Arab nations - especially Egypt, Syria and Saudi Arabia, the leaders of the current moves to start talks in Geneva by spring or summer - want the united bargaining front stitched together by the time U.S. Secretary of State Cyprus Vance begins his Middle East tour in three weeks.

"By that time the Arabs must reach some unified position on Geneva." said Abu Odeh, the Jordanian information minister. "By that time the PLO must be brought into the picture some way or another. That is King Hussein's hope."

The deep bitterness between Jordan and the PLO stems from King Hussein's orders to his army in 1970 to throw the Palestinian guerrillas out of the country after fierce fighting.

The Palestinians have never forgiven Hussein for what they considered a traitorous act by an Arab leader. As an example of the bitterness they felt, they named the terrorist organization responsible for political assassinations and the member of Israeli athletes in the 1972 Olympic games in Munich Black September after the month the Jordanian monarch first moved against the PLO.

Now, weakened politically by the Lebanese civil war, the Palestinians are being forced to make their peace with Hussein.

"It will be hard to swallow," said one PLO worker in Beirut, "but we'll swallow it."

For his part, King Hussein was described by one diplomat here as "a reluctant virgin," running the risk of losing the Israeli-held West Bank of the Jordan River to the Plo in a peace settlement or being blamed by the Palestinians for any concessions he makes on their behalf in peace talks.

"I think they [the Palestinians] are more anxious to start the dialogue with Jordan than Jordan is," Abu Odeh said.

One thing is certain from talks with Jordanian officials here: The PLO will not be allowed to reestablish military bases in Jordan for attacks on Israel the way they did before 1970. It was these bases and the armed Palestinian guerrillas running around Jordan - acting in effect as a state within a state - that led King Hussein to move against them.

It was the same type of Palestinian activity in Lebanon that brought about battles between the PLO and the right-wing Christians who say they will not be happy until the entire PLO military and political aparatus is removed from that country.

Bridging the Gap between the PLO Leadership and Hussein is a Key factor in the Arab dive toward peace talks. While the Arab nations are firm in standing that the Palestinans must be included in Peace talks, Diplomats here questioned how many of their bargaining chips they cared to throw away on the procedural matter of including the PLO as an independent delegation.

"Would [Syrian President Hafez] Assad rather get the PLO to Geneva or get more of the Golan Heights back from Israel? Would [Egyptian President Anwar] Sadat rather get more of the Sinal returned?" asked one Diplomat.

For that reason, observers here and in Beirut said, Egypt and Syria pressured both Hussein and PLO leader Yasser Arafat to come together.

The most pressure was put on the Palestinians, though, one diplomat said. As a result, two high PLO officials here for a meeting last week of the Arab Federation of Parliaments visited Hussein.

Abdou Rabbou, the PLO executive committee member, called that first step "successful" and the PLO's Central Council voted in Damascus last weekend to continue the talks with the Jordanian government.