Louisville aircraft mechanics rejected a deal with UPS late Monday over a tentative contract that would have resulted in higher wages for employees, according to a company spokesman.

Leaders of Teamsters Local 2727, which consists of 1,300 members in the Louisville area, announced in August they had accepted a tentative contract with UPS in which employees would receive raises of about 16 percent with 3-percent annual pay hikes.

But UPS spokesman Mike Mangeot said the deal fell apart Monday.

“UPS is disappointed by the vote result," Manegot said. "Together with Local 2727 negotiators, we established a generous agreement that maintained industry-leading wages and benefits and provided excellent income security for our aircraft mechanics."

Manegot would not disclose the vote total and said the contract is being handled by the National Mediation Board. UPS plans to meet with Teamsters leadership again to determine the next steps in negotiation.

Teamsters Local 2727 President Tim Boyle did not return a request for comment Tuesday evening.

Read more:Union urges Louisville UPS workers to reject new contract proposal

Negotiations between UPS and the Teamsters have been a long and arduous process — they have been negotiating the terms of various contacts for the last four years.

After the last agreement expired in late 2013, employees continued working under the terms of the last agreement, as is common in collective bargaining.

But during that time, aircraft mechanics have aggressively accused the shipping giant of foot-dragging over a new agreement. They picketed at Amazon warehouse sites in the region and protested outside of Senate Majority Leader Mitch McConnell's Louisville home, demanding the Trump administration step up for better pay and benefits for union workers.

The mechanics currently make an average of $50 an hour.

Related:Amazon is raising the minimum wage for US workers to $15 per hour

The group cited Trump's and McConnell's promises that workers would benefit from the corporate tax cut approved last December by Congress resulting in better pay and benefits. UPS reported saving tens of millions of dollars from reduced tax rates, the Courier Journal previously reported.

Also, UPS and the International Brotherhood of Teamsters reached tentative terms on a five-year pact in late June. But roughly 10,000 UPS drivers and package handlers in Louisville and thousands more at UPS freight hubs across the country still need to approve the deal.

UPS is one of Louisville's largest employers with roughly 21,000 workers in the area.

Thomas Novelly: tnovelly@courierjournal.com, 502-582-4465. Support strong local journalism by subscribing today: courier-journal.com/tomn.