If no formula is found in the coming months for peace talks on the future of the Israeli-occupied West Bank, King Hussein of Jordan will move to restructure his kingdom on the east bank, according to authoritative Jordanian sources.
''We may arrange a Jordan from the river to the desert,'' said one official.
This could mean elections for Jordan east of the Jordan River, without the Israeli-occupied West Bank. The now-defunct Jordanian parliament was suspended in 1974. At that time half its members were West Bank Palestinians.
It may also mean new restrictions for people crossing from the West Bank to the east bank via heavily traveled Jordan River bridges, which Israel has left open.
Such moves are being discussed in the highest circles here in the wake of the breakdown of the Reagan peace initiative.
The Reagan proposals called for the return of the West Bank to Jordan, which ruled it before 1967, in return for peace with Israel. In addition, the West Bank and the Gaza Strip would become a Palestinian entity linked with Jordan, thus settling the problem of a Palestinian homeland.
But on Sunday, Jordan abandoned talks with the Palestine Liberation Organization over an agreement that would have enabled them to form a joint Palestinian-Jordanian team to enter negotiations over the West Bank's future. Jordanian officials say PLO proposals did not give priority to saving the West Bank from imminent Israeli annexation. They say the PLO preferred instead to maintain PLO internal unity in the face of many factions strongly opposed to the Reagan plan.
Jordan is unwilling to enter talks without approval of the PLO - recognized by the Arab states as the sole spokesman for the Palestinians - especially since it distrusts United States resolve to persuade Israel to alter its declared intention to keep the West Bank.
One of the King's primary goals in pressing for negotiations was his belief that resolution of the West Bank problem was essential to safeguarding the security of the east bank. Jordanians worry that unless the Palestinian problem is solved, the Arab world may see the east bank as the repository for thousands of hapless Palestinian refugees unwanted in Lebanon, or for West Bankers fleeing Israeli occupation which has become permanent.
The Jordanian authorities also worry that Israel might ''try to unseat'' the King in order to make good frequent claims by Israeli officials that the east bank - whose population is 60 percent of Palestinian origin - is already ''the'' Palestinian state.
Having now resolved he can do no more to try to save the West Bank - at least until the US, the Arab states, or the PLO comes up with some new formula - the King is now determined to protect what he has left.
''We have to organize our own home,'' said one Jordanian official.
The government statement detailing Jordan's withdrawal from talks with the PLO noted pointedly that Jordan ''will work as a member of the Arab League'' in supporting the PLO ''in compliance with the requirements of our national security.''
Informed Jordanian sources say the reference to security means that Jordan will not allow itself to be pressured by Arab countries to accept large numbers of new Palestinians. This, they say, is the responsibility of all the Arab states. The situation is more complicated with West Bankers who hold Jordanian passports. But, say these sources, there is at least some discussion of imposing stricter controls on the Jordan River bridges and limiting the number of West Bankers who seek to settle on the east bank.
However, it would be political dynamite to close the bridges altogether in a country where almost every east banker is linked by family to West Bankers.
The King will now also focus his attention on how to reestablish democratic institutions on the east bank, according to senior Jordanian sources.
The Jordanian parliament was suspended nine years ago after the PLO was declared sole Palestinian representative by Arab leaders, thus presumably preempting the half of the parliament that came from the West Bank. There has been growing pressure both from Palestinians and from indigenous east bankers for restoration of democratic institutions. But this was always postponed until a solution of the West Bank question could be found. With the West Bank put aside, the King seems poised to reassess the delicate issue of participatory institutions for east bankers only.
Finding a suitable formula for restructuring the east bank may be tricky. Prominent indigenous east bankers who believe the country is better off without the 800,000 Palestinians of the West Bank have been congratulating the government for its new stand. They may be eager now to play a larger role. On the other hand, Palestinian east bankers may be anxious about their status in an east bank kingdom.
To calm such fears, the government statement on Sunday stressed that Jordanians and Palestinians are ''one family.'' Moreover, the Jordanians have pointedly kept criticism of PLO chief Yasser Arafat and the mainstream of the PLO to a minimum, and insisted that PLO-Jordanian relations will remain normal and that all PLO offices in Amman will remain open.
However, the new Jordan - if it remains so - will be a far cry from the country which previously described itself as more involved than any other Arab state in regaining lost Palestinian land. The monarchy will still maintain influence and connections in the West Bank. But even if West Bankers should come to Amman to urge the King to continue his struggles on their behalf, informed sources say he would refer them to the PLO or to the Arab states that voted to make the PLO the sole spokesman for the Palestinians.