Virgin Australia opened a spacious new 300-seat lounge with a strong pitch to the corporate sector, moments before Canberra Airport Group unveiled one of the final stages of the $480 million terminal on Wednesday.

Chief executive John Borghetti conceded Virgin must lift its game to compete with Qantas.

For years Virgin complained the Australian government favoured Qantas on the Sydney-Canberra route, now it is using reconfigured Embraer jets, and a new lounge with leather seats and fine dining, to woo senior public servants and business travellers.

''Let's be fair, our product was not as good as it needed to be,'' Mr Borghetti said. ''But the short answer is 'yes' we are getting increased share, it is growing at what we expected, but we also know this [new lounge] will turbocharge that.''

Mr Borghetti said Virgin had increased services to 300 a week, in and out of Canberra, and would continue to add capacity.

''It would be very silly of us to invest all this infrastructure and facilities such as this if we didn't have a plan to get more of the business in Canberra.''

Qantas has 61 per cent of the Canberra-Sydney route, Australia's 12th busiest journey by passenger volume, while Virgin has 35 per cent and Brindabella Airlines 4 per cent.

Infrastructure and Transport Minister Anthony Albanese said the airport, which property developer Terry Snow bought in 1998 for $65 million, was at least as good as any other in Australia and arguably developing into the best in the country.

Airport managing director Stephen Byron said work on the four-year terminal project, which stalled briefly when it was hit by the global financial crisis, had peaked with 500 workers on site.

Work would be finished by Christmas and marked a milestone.

''Yesterday Canberra celebrated her 100th birthday and today we come of age with a gateway that befits the national capital of a modern, sophisticated and innovative nation,'' he said.

Chief Minister Katy Gallagher made a pitch for more international flights, pointing out 163,000 international visitors came to Canberra last year.

Mr Borghetti would not commit Virgin to direct flights.

''At some point, some airline will do it, but I'm not going to tell you what my plans are,'' he said.

Ms Gallagher said the airport's new public art was fabulous, the arrivals area spacious and the departure lounges comfortable and easy to use.

Mr Albanese said being curfew free enabled the airport to expand freight services and provide jobs and economic growth for the ACT and southern NSW.

''And I reiterate the federal government's opposition to developing housing under the flight path at Tralee [south of Canberra].''

He urged the NSW government to reconsider its decision last year to approve Tralee, saying it would be a repeat of mistakes of the past.