RE:
Settlements only "illegal" for Jews
⁜→ P F Tinmore, et al,
Your question is about "sovereign authority." That does one sovereign authority exercise sovereign authority over another territory
(or new territory) in order to make changes:
• Section 2: Acquisition of Territory •
• Dr. Walid Abdulrahim Professor of Law •
The international rules related to territorial sovereignty are rooted in the Roman Law provisions governing ownership and possession. In addition, the classification of the different modes of acquiring territory is a direct descendant of the Roman rules dealing with property.
Territory is the space within which the State exercises sovereign authority. Title to territory is acquired either through the claim of land not previously owned (
terra nullius) or through the transfer of title from one State to another.
[14] Title acquired in the first category is called original title, while in the second category is called derivative title. Modes of original acquisition of territory include occupation, prescription and accretion. Derivative modes include cession (voluntary or forcible), and conquest and annexation. All these modes are dealt with in the following.
(1)
Occupation
Occupation is an original mode of acquisition by a State of a title to a territory. It implies the establishment of sovereignty over a territory not under the authority of any other State (terra nullius) whether newly discovered or abandoned by the State formerly in control (unlikely to occur).
(2)
Prescription
A title by prescription to be valid under International Law, it is required that the length of time must be adequate, and the public and peaceful exercise of de facto sovereignty must be continuous. The Possession of Claimant State must be public, in the sense that all interested States can be made aware of it. It must be peaceful and uninterrupted in the sense that the former sovereign must consent to the new sovereign. Such consent may be express or implied from all the relevant circumstances. This means that protests of whatever means by the former sovereign may completely block any claim of prescription.
As the requirement of adequate length of time for possession is concerned, there is no consensus on this regard. Thus, the adequacy of the length of period would be decided on a case by case basis. All the circumstances of the case, including the nature of the territory and the absence or presence of any competing claims will be taken into consideration.
(3)
Accretion
(4)
Cession
(5)
Conquest and Annexation
Although today conquest is not a legal mode of acquiring title to territory, it does give the victor certain rights under International Law as regards the occupied territory, such as rights of belligerent occupation.
[31] The territory remains the legal possession of the ousted sovereign because sovereignty does not pass by conquest to the occupying State, although it may pass in certain cases where the legal status of the territory occupied is in dispute prior to the conquest.
At present times, acquisition of territory following a war would require further international action in addition to internal legislation to annex. Such further international action would be either a treaty of cession by the former sovereign or international recognition.
Modern examples of annexation following conquest are Israel’s annexation of the Golan Heights and the East Jerusalem, and Iraq’s annexation of Kuwait in 1990. In case of the Iraqi annexation, the Security Council adopted the resolution 662 of 1990 declaring that this annexation “has no legal validity and is considered null and void”, and called upon all States not to recognize this annexation and to refrain from actions which might be interpreted as indirect recognition.
What foreign country has the authority to change the borders of another country?
(COMMENT)
• Disengagement from the West Bank • Quote
Jordan - History - Disengagement from the West Bank
On July 28, 1988, King Hussein announced the cessation of a $1.3 billion development program for the West Bank, explaining that the measure was designed to allow the PLO more responsibility for the area. Two days later, he formally dissolved Parliament, ending West Bank representation in the legislature.
On July 31, 1988 (before the PLO Declared Independence) King Hussein announced the severance of all administrative and legal ties with the occupied West Bank. Accordingly, electoral districts were redrawn to represent East Bank constituencies only. This disengagement decision marks the turning point that launched the current democratic process, and began a new stage in Jordan’s relationship with West Bank Palestinians.
The decision to sever legal and administrative ties with the West Bank allowed Jordan’s electoral law to be changed, redrawing the map to include only East Bank districts. During the same period, mounting economic difficulties led to a spate of rioting in certain parts of the Kingdom. Circumstances had therefore coalesced to produce a situation favoring the resumption of the democratic process King Hussein had initiated early in his reign. In November 1989, general parliamentary elections were held in Jordan for the first time since 1966, ushering in a new era for the institutionalization of Jordan’s democratic experience.
In practice, the "disengagement" left the West Bank and Jerusalem in the hands of the only "Effective Authority" over the area (Israel).

Most Respectfully,
R