The Kurdish-dominated territory, located in an area controlled by the Syrian regime, has been receiving aid airlifts from Damascus since July 2016.
"WFP and UNHCR are in the process of sending humanitarian assistance by road as a trial from Damascus or Aleppo through Menbij to reach Qamishli," according to minutes of a UN meeting of aid agencies in Damascus, Reuters reported.
"This will be the first time UN agencies send trucks to Qamishli directly. Both agencies have submitted a request to the (Syrian) Ministry of Local Affairs and are awaiting approval."
The UN has been requesting permission to deliver aid via land routes from Turkey, rather than airlifts, for months.
Minutes from the aid meeting show that the Syrian regime's Foreign Ministry would approve use of the crossing with Turkey, via Nusaybin, provding the UN seeks approval from Turkey as well.
Turkey is, however, hostile to the main Kurdish YPG militia which operates in northern Syria.
The new land route was apparently opened up after recent advances by Syrian regime forces in the northeastern region.
Last year, the UN said that people living in the Hassakeh province had been been cut off from food and other supplies for more than six months.
The city of Qamishli is split into Kurdish and regime territories, while Washington-allied Kurdish militias and the Islamic State group are fighting for control of Hassakeh province.