The condition conflicts with Hamas's position that Israel must withdraw from all Gaza territory after a ceasefire.
Speaking after the return of Israeli negotiators from talks with mediators in Qatar, Netanyahu said Israel needed control to stop weapons reaching Hamas from Egypt -- one of four conditions for a deal with the Palestinian militants.
He did not say if the measure would be permanent. But it is the first time Israel has insisted on retaining control of the Palestinian side of the Rafah border crossing with Egypt and the so-called Philadelphi corridor along the border.
Netanyahu said Israel's negotiators, led by Mossad intelligence chief David Barnea, went to Doha to defend what he called four "ironclad principles", with the key condition that Israel be allowed to keep fighting until its war aims of destroying Hamas and bringing home all hostages are achieved.
Netanyahu reaffirmed the others: stopping weapons reaching Hamas from Egypt -- "first and foremost by Israeli control of the Philadelphi axis and the Rafah crossing" -- not allowing militants to regroup in northern Gaza and ensuring a "maximum" number of hostages are freed.
While the United States has expressed "cautious optimism" over the Qatar talks, Netanyahu vowed to keeping fighting Hamas with "full force", calling it a "sacred mission" to bring back hostages seized in the October 7 attacks.
The attacks on southern Israel resulted in the deaths of 1,195 people, mostly civilians, according to an AFP tally based on Israeli figures.
The militants also seized 251 hostages, 116 of whom remain in Gaza, including 42 the military says are dead. Some 105 hostages were freed during a one-week truce in November.
Israel's retaliatory offensive has killed at least 38,345 people in Gaza, also mostly civilians, according to the Hamas-run territory's health ministry.
"Ambiguity and hesitance did not bring about our achievements to date, and they will not bring about achievements in the future," Netanyahu said.
"I am committed to an outline for the release of our hostages, but Hamas terrorists continue to insist on demands that contradict the outline and threaten Israel's security," he added.
