The Jordanian government hopes that US Secretary of State George Shultz's efforts in the Lebanese-Israeli negotiations will eventually give a needed push to the stalled Reagan peace plan in Jordan.
But officials and well-informed sources in Amman stress that the push is contingent on a ''tangible'' demonstration of US resolve and effectiveness in securing an Israeli withdrawal from Lebanon and a freeze on settlements on the Israeli-occupied West Bank.
''To us things are clear. If Mr. Shultz is able to get things moving, I think we'll be very happy,'' Walid Tash, secretary-general at Jordan's Foreign Ministry told The Christian Science Monitor.
''We would like to see positive steps which we would consider as the spearhead to any process that we may go into.''
US success in the Lebanon negotiations is seen as possibly strengthening the position of Palestine Liberation Organization (PLO) moderates who favor permitting Jordan's King Hussein to enter talks. But it is not known how the major opponents to the Reagan plan - Syria, the Soviet Union, PLO extremists, and Israel itself - will react.
It is not clear, sources say, that even with US success in Lebanon and efforts on the West Bank the PLO would allow the King to enter the US-sponsored peace process. He is not expected to enter the talks without receiving PLO approval.
The central committee of PLO chief Yasser Arafat's Al Fatah, the largest subgroup within the PLO, voted April 25 in Tunis to support moves by Mr. Arafat to restart the Jordanian-PLO talks. Analysts in Jordan see the vote as an expected expression of goodwill.
Mr. Tash declined comment on the Fatah vote but said he felt it would be ''premature'' to resume Arafat-Hussein talks before seeing the outcome of the Shultz effort.
''If Mr. Shultz does anything in Lebanon, he should do it to impress the Palestinians, not the Jordanians,'' a Jordanian observer said.
King Hussein was poised for a central role in bridging the Reagan peace plan with aspects of other Arab and United Nations plans for peace in the Middle East. The process fell apart amid growing doubt in the Arab world about US resolve to influence Israeli policy.
Mr. Tash said that, had the US successfully exerted pressure on Israel earlier, ''there would have been a more conducive climate for the other component - the Jordanians, the Palestine Liberation Organization, and the other Arabs - to move more forcefully'' in support of the peace initiative.
Officials in Amman also say time is running out. ''The King is working from the fundamental principle that the worst position for Jordan is to do nothing at all,'' a political observer in Amman said.
The Jordanians say the rapid expansion of Jewish settlements on the West Bank and the steady deterioration of the atmosphere in the occupied territories not only contribute to the tightening of Israel's grip on the land but also encourage a new flood of Palestinian refugees to the east bank of the Jordan River.
In the worst case the Jordanians fear Israeli West Bank policy could lead to a breakdown of peace efforts and usher in a new era of terrorism in the Mideast, or even result in another war.
Mr. Tash said the general feeling in the Arab world toward the US is one of ''doubt.'' Jordan has adopted a ''wait and see'' posture regarding the stepped-up US efforts in Israel and Lebanon, he said.
His comments come at a time of intense diplomatic activity and debate within the Arab world and within the PLO itself. Last week King Hussein dispatched Foreign Minister Marwan Qasem and Information Minister Adnan Abu Odeh to seven Arab capitals to communicate Jordan's position on the peace process. Some political analysts in Amman see the shuttling of the Cabinet members as an effort to help gain support for Jordan's peace options. It is also seen as an effort to gain help in persuading the PLO that time is short to join the peace process.
One observer said: ''If the US does something concrete [in terms of a Lebanon settlement] the PLO will come under increasing pressure (to join) not just from the Jordanians but (also) from the Arabs.''
But another source said, ''If Shultz fails in his trip, this will be the death blow to the Reagan plan. . . . It hinges completely on the success or failure in Lebanon.''
In recent communications with Gulf and Arab heads of state the Jordanians emphasize that in asking to represent the Palestinians, Jordan is not challenging the 1974 Rabat Arab summit decision that the PLO is the sole representative of the Palestinian people.