Crews arrived with heavy equipment on Friday at an occupied protest zone in Seattle, ready to dismantle barriers set up more than a week ago by demonstrators.
However the work was halted when some protesters resisted by climbing on top of the makeshift structures.
Stefanie Formas, a spokeswoman for Mayor Jenny Durkan, said the city's goal is to improve access to the area for residents.
She said city officials would discuss plans later in the day with protest organisers.
The collective of protesters, activists, educators and volunteers in the Capitol Hill Organised Protest was formed after clashes with police who tear-gassed people protesting the police killing of George Floyd in Minneapolis.
Ms Durkan has expressed support for the protest, calling it “a peaceful expression of our community’s collective grief and their desire to build a better world.”
But following several shootings in the area, Ms Durkan said the city would wind down the protest zone, at first by encouraging demonstrators to leave.
In addition, she said police would return to a nearby precinct that was abandoned following clashes with demonstrators.
The work crews intended to remove the barricades, not protesters, Sam Zimbabwe, city transportation director, told local journalist Omari Salisbury, who has been live-streaming the protest.
Workers were preserving artwork that had been painted on the wooden barricades, he said, adding that the department would work to return it to the people who created it.
“We're not trying to have conflict,” Mr Zimbabwe said.
A number of protesters remained camped in tents outside the East Precinct.
The city has not given a timeline for officers' return to the building except to say it would be in the near future.
Protesters have called for cutting the police budget 50 per cent and spending the savings on community health and other programs.
The mayor has proposed a vastly more modest cut of $20 million to help balance the city's budget through the end of this year.
