The first Enterprise train testing took place at Belfast Grand Central Station on Sunday morning, ahead of the new transport hub launching all of its rail services officially.

Translink said that the flagship service to Dublin will run hourly and will see 15 trains leave the £340m travel hub for the Republic of Ireland every day – a total of 30 running in both directions.

A spokesperson for the public transport provider added: “This move will make it easier, more convenient and flexible for people to consider the train as their sustainable travel option and help advance climate goals.”

It has been speculated that direct rail services between Belfast and Dublin could properly begin on October 7, after cross-border tickets were advertised from that date on Irish Rail’s website.

However, Translink have still not revealed an official date for when trains will start running from Grand Central Station, which opened for bus services only on September 8.

The new £340m public transport hub opened in the centre of Belfast with the start of bus services. Image: Arthur Allison/Pacemaker Press.

Translink says train services will commence operation from the new station once the firm has received the relevant safety certification.

But, irishrail.ie only lists the service going as far as Lanyon Place — not quite as far as Belfast’s new Grand Central Station.

The station is so far only offering bus services while work continues on railway tracks.

Currently, those travelling from Belfast to Dublin on the Enterprise service have to board a bus to Newry, where the journey can continue via train.

Translink’s group chief executive Chris Conway previously said train services from Belfast Grand Central Station are scheduled to begin in “early autumn”, although he did not give a specific date.

Translink CEO Chris Conway welcomes impending launch of new Belfast station

Speaking on the BBC’s Nolan Show on Friday, Mr Conway said: “Everyone will want to make sure that everything we do is safe so it is important that we do everything with due diligence. We hope to be able to announce a date for opening very soon.

“When we talk about construction, we talk about the railway system. Most people come in and see the station but there is a railway system which sits in behind that. We have training going on at the minute and have trains on that network with staff to do training.

“We are nearly complete on the training and I hope that we will be able to announce something very soon in collaboration with the safety authority.”

When asked how soon he could make an announcement, Mr Conway emphasised that the company want to make sure things are done “properly and diligently” and thus he could not give an exact date.

“We are working with the safety authority. There is always a bit of toing and froing on that and it is important that they have the time to do that process correctly,” he noted.