Negotiations for a new enterprise agreement has turned into a protracted dispute with the March 29 deadline to strike a deal fast approaching.

On Friday, PCKT locked out its workers for the third consecutive nine-day period, which would end on March 18.

Combined with earlier lockouts and strike action, the workers have not been inside the plant since January 18.

Mr O'Connor visited the locked-out workers at Port Kembla on Wednesday and said he didn't believe a dispute should go on for this long.

"This matter has been going on for too long,"  Mr O'Connor said.

"We should have a system where matters are resolved much quicker."

While part of the blame lay with the insufficient powers of the Fair Work Commission, Mr O'Connor suggested the actions of PKCT had also contributed to the dispute.

"I understand that companies have economic pressures but with a relationship you've got to be open and frank about what you need to do," he said.

"What you can't keep doing is moving the goal posts. The history of this dispute as I can see it is every time they get close to resolving the matter the employer has moved the goalposts and that shouldn't happen."

READ MORE: Coal terminal dispute could become a political issue

Mr O'Connor said Labor would be "disappointed" if PCKT did not "show any concern for resolving this matter".

"It’s not about [political] pressure, it's about focusing on a problem and really calling on the parties to resolve it," he said.

"Right now the ball is in the employer's court and we'd like to see them make the move to resolution."

CFMEU Southern District Vice President Bob Timbs felt Mr O'Connor's visit did in fact send a message to PKCT.

"Brendan O'Connor's visit today speaks volumes about how dirty this dispute is becoming," Mr Timbs said.

"When you get national attention such as this it should be a real wake-up call for South32 and PKCT to have a real good look at what they’re doing to the workers at Port Kembla Coal Terminal."

PKCT was contacted for comment.