A union spokesperson said Pacific National freight trains including coal trains to the Port of Newcastle would resume at 3am on Saturday.

In a statement on Friday evening, the union said the company had agreed in-principal to an enterprise agreement - a move which will see an end to the company's lock out of workers.

Pacific National issued a short statement a little after the union, saying the company "today reached an in principle agreement with the union".

"This is a good outcome for Pacific National's frontline workers, shareholders and customers across the freight sector who rely on Pacific National's rail services to deliver what matters," the statement concluded.

RTBU NSW Locomotive Division Secretary, Farren Campbell said the in-principal agreement reached today is a good step forward and will allow trains to get back on the tracks.

"Its bitterly disappointing that it went down this path, but it's great that common-sense has finally prevailed and the company has come to the table and agreed in-principal to give workers the fair wages and conditions they deserve," Mr Campbell said.

"Pacific National members will now of course have to vote on the enterprise agreement, but today's movement from the company means the lock out is off and we can get trains moving again.

"Rail workers shouldn't have to take industrial action to ensure we get safe trains and fair wages and conditions. It's disappointing that it got to this point, but it's good that we're now moving in the right direction.

"This is a win for workers and a win for everyone who relies on Pacific National's services."

THE industrial dispute between the state's biggest freight train company Pacific National and the Rail, Tram and Bus Union has entered its second day, stopping coal shipments with a potential value of $100 million or more a day.

As the Newcastle Herald reported yesterday, the RTBU says Pacific National (PN) has "selectively locked out" hundreds of locomotive drivers in its coal and bulk (non-containerised) cargo division.

A union spokesperson said the industrial action had widened today, Friday, because PN had sent letters of demand to staff employed as terminal operators, as well as the drivers who were the only ones involved in the original "lockout".

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"Terminal operators are drivers who don't leave the depot, and our industrial action was originally only for train drivers," a union spokesperson said this morning.

"By sending the letter, apparently inadvertently, to the terminal operators, they have effectively drawn them into the dispute and our members are within their rights not to work.

"They've been ringing the terminal operators one by one asking them to come in, but our understanding is that many have not."

The union spokesperson confirmed that those who were not working were on strike and would not be paid.

Although the dispute is state wide, much of the impact would be in the Hunter, where coal and grain is rail-hauled to the Port of Newcastle for export.

By coincidence, rail track operator Australian Rail Track Corporation (ARTC) had closed the main northern line between Narrabri and Newcastle on Tuesday for routine maintenance that was scheduled to end at 6.30 this morning.

This had minimised the external impact of the Pacific National stoppage, but the union spokesperson said the fact the system was operational again added to "the urgency" of the talks.

The spokesperson said "assisted bargaining" that began in Newcastle yesterday with the involvement of Fair Work Commission's Deputy President Tony Saunders resumed this morning.

The spokesperson said all parties knew what was at stake in terms of the lost business while industrial action was under way, and the main sticking point remained "pay.

The lockout controversy became public knowledge on Thursday morning when the union announced its members had been locked out for enforcing a protected industrial action in the form of a ban on driving trains the union says are short of designated safety equipment.

PN responded by saying the union was using "outdated" standards in arguing this equipment should be on every loco in a multi-loco freight train.

The union said the company had sent the above-mentioned letters to employees saying that if they were not willing to do all of their duties, they were not wanted at work.

Although PN disputes the term, the union says this meets the definition of a lockout under the relevant section of the Fair Work Act.

The Pacific National lockout follows on the heels of tug company Svitzer moving to lock out its tug crews in 17 ports including Newcastle - a development that was stopped last Friday when a full bench of the Fair Work Commission ordered a six-month suspension of industrial action by either the company or the three unions involved in the dispute.

On recent prices for Hunter coal, the amount of product moved, on average, from the mines to the port, is worth at least $150 million, with the Minerals Council of NSW putting the figure at $200 million a day.

Pacific National is the biggest coal haulier in NSW with up to two-thirds of the NSW market, meaning the coal it would haul, on average, every day, could be worth $100 million or more.

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