OTTAWA — Canadian border officials began a partial strike on Friday that threatens the flow of trade between the United States and Canada and could upset a plan to allow American tourists from Monday to visit their northern neighbor for the first time. times in 16 months.

Overnight talks between the union representing approximately 9,000 Canada Border Services Agency employees and the Canadian government failed to produce a new deal until 6 a.m. Eastern time Friday deadline .

The Public Service Alliance of Canada, which represents customs and immigration officers, said frontline officers will reduce the amount of work done at border crossings and airports and warned that the slowdown in work could cause long and unavoidable delays for shippers and travelers at Canada’s borders. .

A union spokesperson said the bargaining team had been mediating with government negotiators “all night and until this morning, and we are giving them a little more time to negotiate at the table.” The spokesperson said that standard work actions are now underway at border crossings and airports across the country.

“The government is still at the table and will not back down,” a spokesperson for the Treasury Board of Canada, responsible for staffing in the public service, said on Friday. A mediator was called in mid-week to help resolve disputes, which the union says focus on working conditions and pay.