N. Ireland political impasse
The main pro-UK party in Northern Ireland has boycotted the devolved assembly in Belfast since February 2022. AFP

Talks between London and Northern Irish parties aimed at restoring devolved government in the region failed Monday, days ahead of a deadline for calling an election and a mass public-sector strike.

Over 150,000 of Northern Ireland's 220,000 public service workers are expected to join a coordinated day of strike action by 15 unions Thursday over long held-up pay increases.

The mass strike by public transport staff, nurses, civil servants and teachers is billed by unions as the biggest in the history of Northern Ireland and is expected to cause widespread disruption.

UK Northern Ireland Secretary Chris Heaton-Harris told reporters in Hillsborough near Belfast that a GBP3.3 billion ($4.2 billion) package offered to the parties last month would be available on condition that the Northern Ireland Assembly at Stormont -- suspended almost two years ago -- restart.

"This money would allow Stormont to give workers a pay award," said Heaton-Harris, who is responsible for setting budget allocations for public services.

"It is time for the talking to finish and it is time for Stormont to get back to work," he said.

Thursday's public-sector strike also coincides with a legal deadline for the restoration of power-sharing at Stormont.

If no executive is formed by Thursday, Heaton-Harris is legally obliged to call an early election for the assembly, though he is widely expected to push back this deadline.

The largest pro-UK party, the Democratic Unionist Party (DUP), withdrew from the Stormont Assembly in February 2022 because of post-Brexit trading rules it said undermined the region's place in the wider United Kingdom.

The main unions say the money for public-sector pay rises should be released as soon as possible regardless of the dormant assembly, while the DUP accuses London of using industrial unrest as a lever to end the party's boycott.

"You don't need to have a functioning Stormont in order for (Heaton-Harris) to use the temporary powers that he has," DUP leader Jeffrey Donaldson told reporters, urging London to "make those public-sector pay awards".