Wellington City Councillors agreed in principle to adopt a sister-city relationship with Canberra on Wednesday, marking the beginning of a new chapter in the relationship between the Australian and New Zealand capitals.

The agreement, which is expected to be formalised when a delegation headed by ACT Chief Minister Andrew Barr visits Wellington in July, could see both cities promoted to Asian tourists as a "two-capital holiday", according to a report tabled to council.

It could also see the National Museum of Australia and New Zealand's national museum Te Papa share exhibits, expertise and even staff.

The sister city relationship comes after Singapore Airlines announced it would begin operating direct flights between Canberra, Wellington and Singapore in September.

Mr Barr said the connecting flights were only one of the "emerging connections" between the two cities and they would lead to more trade and investment opportunities for both.

Canberra is also set to host a match between A-League football teams the Central Coast Mariners and Wellington Phoenix next season, as well as a one-day-international cricket match between New Zealand and Australia in December.

The idea was raised when Wellington mayor Celia Wade-Brown visited Canberra last month and received support from both sides of the ditch.

Mr Barr said he would be taking the proposal to the ACT Legislative Assembly in June.

The new relationship would see universities working bilaterally to attract students to both cities, according to the council report.

It could also see the Canberra Woodlands and Wetlands Trust collaborating with Wellington's Zealandia wildlife sanctuary on biodiversity issues and the two cities comparing natural disaster responses.

- With stuff.co.nz