Winnipeg Purolator customers are trying to figure out how to send and receive important packages, after the courier company suspended shipping amid the threat of a strike.

In a press release, Purolator said it was suspending shipments Tuesday, but expected those already in the system would be delivered.

Purolator said it made the decision to protect customers from being negatively impacted.

Meagan Berry showed up at Purolator's Sargent Avenue location to send an insect specimen to a lab in Mississauga, Ont.

She works for a pest control company, and makes shipments with Purolator daily.

Berry said she doesn't know what she'll do now, because it's important she gets the package to the lab so her company can help her customer quickly.

The union representing employees, Teamsters Canada said on its website Purolator's final offer was rejected by members Sunday. A strike deadline has been scheduled for 4:30 p.m. on March 29.

"On March 26, as a result of this rejection, the union served a 72-hour notice of strike action to the company," the union said.

“We are deeply disappointed in the outcome of Sunday’s vote and in Teamsters Canada’s decision to issue 72-hours’ notice for strike action,” said Ken Johnston, vice president of human resources and labour relations at Purolator.

“However, we look forward to returning to the bargaining table, working diligently to negotiate a new agreement and getting back to delivering our customers’ packages.”

The union, which represents more than 8,000 workers, told CTV News Tuesday it would not be doing further interviews because negotiations had resumed.

“The Federal Mediation and Conciliation Service (FMCS) has summoned the parties to a meeting today to avoid a strike. We look forward to finding common ground with the employer,” said Stéphane Lacroix, public relations director in an email.

The shipping company has eight terminals in Manitoba. Purolator would not disclose how many employees or shipments may be affected by a strike in the province.

"For competitive reasons, we do not disclose details on employees and volume," Corporate Communications Director Karen White-Boswell said in an email to CTV News Tuesday.

She said the company did not have a spokesperson to speak about the issues of the labour dispute.

"As we return to the bargaining table today, Purolator remains hopeful we’ll reach a new agreement without a labour disruption," White-Boswell said.