The federal government is considering outsourcing some diplomatic work at missions abroad as Canada’s striking Foreign Service officers give little indication they are prepared to abandon the picket lines and return to their jobs.

Sources tell CTV News that the government is considering replacing some Foreign Service officers at various missions abroad with local, cheaper hires.

Treasury Board President Tony Clement, the government’s representative at the contract negotiations, said Tuesday: “We are looking at all our options, and that includes things that have not been done in the past,” but would not directly say that this includes replacement workers.

“I can’t confirm or deny that at this juncture,” Clement said.

Tim Edwards, president of the Professional Association of Foreign Service Officers, said the fact that replacement workers are being considered, “shows we’re getting deep under his skin. It shows we’ve got his attention.”

Edwards, however, was skeptical that the government would use replacement workers.

“International effectiveness, negotiating skills, communications skills, the whole package,” Edwards told CTV News. “You can’t simply replace that at the drop of a hat.”

The war of words followed ramped up efforts on the part of the striking diplomats in recent days, including rallies outside the Prime Minister’s Office and at Canadian missions around the world Tuesday. On Monday, about 150 visa officers were the latest to take part in a rotating job action, which affected about 15 overseas missions.

The union increased its strike action after talks aimed at working out binding arbitration broke down last week.

The strike is nearing the five-month mark.

CTV News obtained an internal email written by the deputy minister of foreign affairs to all staff that suggests tensions are also escalating between striking workers and staff who aren’t on the picket line. The memo warns of “zero tolerance” for anyone who tries to intimidate or threaten their peers.

Although the government and its Foreign Service workers are at an impasse, the opposition said the concept of outsourcing diplomats raises a number of red flags.

“You can’t just pick people off the street or out of one office and stick them into an environment, which involves considerable security requirements, representing Canada internationally,” said NDP MP Jack Harris.

Apart from security concerns, the strike is also having an impact on the Canadian economy, as visa applications for tourists, seasonal workers and international students are in limbo.

“It’s causing a great deal of concern and anxiety within our foreign service,” said Liberal MP Kevin Lamoureux said. “And it’s costing our economy money.”

With a report from CTV’s Richard Madan and files from The Canadian Press