Heavy equipment operators have been told to go back to work immediately as a trade group agreed to lift a labor lockout that has stalled progress on about 160 road construction projects across the state for nearly four weeks, Gov. Rick Snyder's office announced Thursday afternoon.

The Michigan Infrastructure & Transportation Association and Operating Engineers Local 324 have made a short-term deal Thursday morning to resume work without a contract to at least finish the 2018 construction season. More than 1,000 union workers were booted off construction sites Sept. 4 when MITA instituted a "defensive lockout" in hopes to get OE 324 to sign an industry-proposed contract. A previous five-year contract ended June 1.

The trade association and union told Snyder's office that construction would resume Friday morning, but some activity reportedly began as early as Thursday.

Snyder's office declined to release documents related to the agreement. As laid out in a news release from the state, short-term plans include:

MITA will end the lockout on all projects;

The union will have its workers report to work immediately;

The priority for work will be for projects that can be completed prior to significant winter weather arriving;

Other projects will continue for as long as possible, including work to prepare them for safe winter travel if they cannot be completed;

Contractors and OE 324 will use professional mediation through the winter to help them negotiate a new contract.

Any projects that cannot be finished in November, which is when the construction season generally ends, will be managed by the Michigan Department of Transportation, the release said. Plans to bring in the Michigan National Guard to continue construction have since been called off, but Snyder spokesman Ari Adler said the Guard "stands ready and able to step in if needed."

After aides met with both parties last week while the governor was on a trade mission in China, Snyder first met with the dueling parties Tuesday to try to hammer out a resolution. That meeting ended without results, but Snyder on Thursday applauded the breakthrough. The governor's staff continued talks with MITA and OE 324 after the Tuesday meeting.

"The vital work of getting Michigan's roads repaired should not have stalled, but the important thing now is that projects will be getting back on track," Snyder said in the announcement. "A long-term solution to the contract negotiations still needs to be worked out, but that can and should be done after this construction season is completed."

MITA said it understands the "frustration this has caused," but would continue to back its contractors.

"We appreciate the Governor's commitment to resolving this issue in a satisfactory manner for both sides so we can get these road projects underway again," MITA Executive Vice President and Secretary Mke Nystrom said in the release. "Our members will work with MDOT to get things wrapped up as quickly as possible and get lanes open again for motorists."

OE 324, which is adamant that it does not want to sign a new contract with the trade association so it can deal directly with contractors, said its workers look forward to getting back to work. Since the last contract expired June 1, its members continued to work the projects until the Labor Day holiday. The lockout began the day after.

"We still have issues to work out and will represent the best interests of our members throughout those negotiations, as we always have. We appreciate Gov. Snyder's willingness to not take sides and to remain focused on finding a way to get the work done," OE 324 President Ken Dombrow said in the release.

MDOT is evaluating construction timelines, extensions and financial penalties of each project. Schedule changes will be up to contractors with supervision from MDOT, Adler said.