Of that, travel for Mr Barr himself plus his two ministerial staff amounted to $20,080.

The visit, organised by Commissioner for International Engagement Brendan Smyth, included four public servants as well as Mr Barr and his staff.

A government spokesperson said final costs were not in, but the trip was expected to total $68,000, including an "investor showcase", where 15 Canberra businesses had pitched themselves to Singapore businesses. The amount included the estimated cost of support for the Canberra businesses which travelled.

A detailed itinerary shows that Mr Barr, his two staff and Mr Smyth stayed at the JW Marriott, arriving early on Saturday morning after the overnight trip from Canberra. Saturday and Sunday were scheduled for an optional self-guided "sites of architectural significance tour", and a visit to Singapore's nearby "Gardens by the Bay", a futuristic garden.

Meetings began on Monday, when Mr Barr visited Australia's high commissioner, former Canberran Bruce Gosper, Singapore's trade minister and Singapore Airlines chief Goh Choon Phong, before a tour of the Changi airfreight centre, where Mr Barr said he saw facilities for handling perishable freight. In his meeting with Mr Goh, he had reaffirmed the government's commitment to funding for marketing, discussed other ways to "drive traffic in both directions", and discussed more frequent services including freight. He also met Toll on the subject of freight.

On Tuesday, Mr Barr laid a wreath at the war memorial to mark Anzac Day and visited Singapore's NEC Laboratories, where his spokesman said he had toured the "innovation lab" and discussed "opportunities for collaboration on smart city technologies".

He met senior Singapore Tourism officials, then met Singapore rugby union authorities with the Brumbies chief Michael Thompson, a meeting that a government spokesperson said had resulted in a game between the Brumbies and the Asian Barbarians in Singapore in June.

On Wednesday, he met with BNP Paribas Wealth Management manager Daniel King, who he said had helped organise investment for Canberra businesses, and with VS Industry Berhad, which had invested in the Canberra-based autonomous car technology company Seeing Machines.

He opened an event to pitch Canberra start-ups to investors, before meeting the Australian Chamber of Commerce and visiting an Australian international school.

A director of the Canberra Innovation Network, Nick McNaughton, said there had been a good response from the meetings between Canberra and Wellington start-ups and the 80 investors. There had since been 125 investor contacts, including 12 inquiries to CSIRO spin-off the Healthy Grain, which markets a non-genetically modified strain of barley.

As to Mr Barr's involvement, Mr McNaughton said, "We understood he was going and we wanted to synchronise this event with his visit", because, as chief minister, he was a drawcard.

"Singaporeans like to see government support for the start-up community," he said.

Mr Barr's only evening event in Singapore was on Wednesday evening, when he attended an "investment networking event" at the high commissioners' residence.

Mr Barr's spokesman said about 100 mainly Singapore-based guests had attended the networking event, along with 40 Canberra delegates and about 10 from the New Zealand high commission. About 110 Singapore investors had registered to attend the investor showcase.

On Thursday, Mr Barr toured SingTel NCS and toured Austrade's "landing pad" which helps Australian start-ups in Singapore. In the afternoon, he visited the Singapore Airlines training centre, as he has done before.

Mr Smyth did not answer questions directly about the trip, but referred them to the departmental media contact. The spokesperson pointed to ongoing work to establish Canberra as a freight hub for exports including the region's produce, "cooperation on future horticultural opportunities" which was related to the Gardens by the Bay visit, and the launch by Canberra's Skoolbo of television program Preschool Play during the visit.

Correction: An earlier version of this story said the Healthy Grain marketed a genetically modified rice. The Healthy Grain's products, including a barley strain, and in development an ultra-low gluten barley and a black rice, are non-genetically modified.