Chief Minister Andrew Barr said an express service with fewer stops would immediately improve travel times on the route without the need for expensive and intrusive upgrades.

The territory will also look to begin talks on possible future upgrades of the ageing Canberra station at Kingston, which is owned by the NSW government.

Passenger numbers were up by almost one-third on the Canberra-to-Sydney line this year, with 23,700 passengers taking a trip in either direction on average each month.

Mr Barr said he would raise the issue of an extra service with the NSW government, touting it as a practical short-term project to improve travel time between the two cities.

"The current three services a day, I understand, are almost always sold out, so there is potentially a case for either more carriages to be added to those services, so there's some extra seats, or an additional service offered each day," Mr Barr said.

Mr Barr said an express service that stopped less frequently between Canberra and Sydney could deliver a faster travel time without the need for expensive or intrusive infrastructure upgrades.

"Then there's a sort of big network decision that the NSW government needs to make as part of their metro transport review as to what priority the CountryLink trains are given once they enter the suburban network," he said.

Trains from Canberra can sometimes be held up once they enter the suburban network because electric suburban trains are given priority on the line and through stations.

Just under 68 per cent of trains on the Canberra line ran on time in 2022-23, down slightly from 73.9 per cent in 2021-22, the operator's annual report shows.

Mr Barr said he would continue to raise the issues of the Canberra-Sydney rail line with NSW Premier Chris Minns and the state's Transport Minister, Jo Haylen.

The Chief Minister said there was the prospect of a good conversation on the future of Canberra's railway station. The NSW government owns

"Railway station redevelopment is something the NSW government do very regularly. And is obviously part of their Sydney urban intensification agenda, so I think they'll have some good insights on how those sorts of projects are undertaken," he said.

Mr Barr in November revealed he had put upgrades to the line on the ACT's list of priorities for the National Capital Investment Framework, which guides joint Commonwealth and territory funding.

The ACT called for immediate consideration of funding feasibility investigations for upgrades to the rail link under the investment framework, the Chief Minister revealed in a Legislative Assembly debate.

"I've raised the need to improve this rail link in my first letter to [NSW Premier Chris] Minns following his election. I've also personally discussed the matter with him and with his transport minister, Jo Haylen," Mr Barr said.

Mr Barr said at the time upgrades to the rail line would require all three governments - the Commonwealth, the NSW and the ACT - to work together.

"But I am encouraged by the early responses from both my NSW and federal counterparts," he said.

The NSW government has ordered new trains to replace its ageing regional train fleet, including the 23 Xplorer class carriages which operate between Sydney and Canberra.

"Production of the 29-train fleet is underway and a timeline for their delivery will be confirmed once the testing and assurance phase of the manufacturing is complete,"

NSW Regional Transport and Roads Minister Jenny Aitchison in December said the state government was pleased passengers were embracing regional train services, which had been attributed to affordable fares and an advertising campaign.

"People are recognising that it is a unique, cost-effective way to sit back and enjoy the ride, taking in the stunning scenery out the window, without the stress of driving or catching a plane," Ms Aitchison said in a statement.

"We also see, particularly for popular routes like Melbourne and Brisbane, are valued because passengers arrive right in the heart of the city, without the need to transfer from an airport."

In March, a leading international rail expert said a high-speed rail link would drive economic wealth in the broader Canberra region by drastically improving the area's connection to Sydney, and could be completed by 2045 if work began on the project now.

Professor Andrew McNaughton, who prepared a report for the NSW government on the future of rail connections in the state, said that unreleased modelling showed there was a genuine case for high-speed rail between Sydney and Canberra, which would "take off" as a city region.