The highway between the NWT and Alberta remains closed to regular traffic but has been opened for northbound trucks carrying "essential goods."
The territorial government's Department of Infrastructure made the announcement on Thursday morning.
As one of just two highways connecting the NWT to the south, Highway 1 – which becomes Highway 35 in Alberta – is an arterial route, vital for resupply of the territory's communities.
A growing northern Alberta wildfire closed the highway in both directions earlier this week, with southbound traffic held at Enterprise and northbound traffic held at High Level (though local traffic was able to reach Zama City, AB).
"High Level RCMP has advised that Alberta Highway 35 and NWT Highway 1 has reopened between High Level and Enterprise for ONLY northbound commercial vehicles with essential goods and services," the Department of Infrastructure tweeted on Thursday.
"All other vehicles are prohibited.
"This is to allow for the movement of essential goods and services. We do not have a timeline for when the highway will reopen to all vehicles."
On Wednesday, major stores in Yellowknife told Cabin Radio they had no immediate concerns regarding the highway closure's impact on supplies.
The wildfire, which originated near Steen River, was estimated at some 17,500 hectares in size early on Wednesday.
A CN Rail bridge in the area was reported to have been destroyed by the wildfire later that day.
CN Rail could not be reached for comment by Cabin Radio.