An ongoing dispute between Lyttelton Port Company and the majority of its workers appears to have finally reached a resolution.

The port and the Rail and Maritime Transport Union have reached an agreement in principle for terms of the settlement.

This comes after weeks of attempted negotiations and industrial action.

As a result, the union has lifted all strike notices and the port has withdrawn its lockout notice.

RMTU organiser John Kerr says it's a win-win.

"The port company has said this is good for everybody.

"It's good for their customers, it's good for our members, it's been dragging on a while and it's a good result."

The agreement still needs formal ratification from the union members - but Port CEO Peter Davie says it's a positive step.