The Government was also reviewing a threat management plan already in place for the dolphins, with the programme to be informed by a marine research and advisory group of scientific and stakeholder experts.
In its latest report, released today, the IWC Scientific Committee welcomed new research around the dolphins' welfare but pointed out that no new management actions had been enacted since 2013.
"Given the information presented this year, the committee concludes, as it has repeatedly in the past, that existing management measures in relation to bycatch mitigation fall short of what has been recommended previously and expresses continued grave concern over the status of this small, severely depleted subspecies," members reported.
"The human-caused death of even one individual will increase the extinction risk."
In its recommendations, the committee re-emphasised that the "critically endangered status of this subspecies and the inherent and irresolvable uncertainty surrounding information on most small populations point to the need for precautionary management".
Further, it re-iterated its previous recommendation that "highest priority" should be assigned to immediate management actions to eliminate bycatch of Maui's dolphins, including closures of any fisheries within the range of Maui's dolphins that were known to pose a risk of bycatch to dolphins.
Thirdly, it noted that the confirmed current range extended from Maunganui Bluff in the north to Whanganui in the south, offshore to 20 nautical miles, and it included harbours.
"Within this defined area, fishing methods other than set nets and trawling should be used.
"The committee again respectfully urges the New Zealand Government to commit to specific population increase targets and timelines for Maui's dolphin conservation, and again respectfully requests that reports be provided annually on progress towards the conservation and recovery goals."
WWF-New Zealand's head of campaigns, Peter Hardstaff, said the conclusions of the international science panel were clear: "more incremental steps and more research are not good enough".
"We need action to fully protect Maui's dolphins across their entire range. The Government should do the maximum possible, rather than the minimum it can get away with."
Mr Hardstaff called on the Government to help affected fishers transition to dolphin-friendly methods and extend the ban on set netting and traditional trawling to cover all of the Maui's dolphins known range.
"The world is watching us, we need to do the right thing and save these dolphins, which are only found in New Zealand, with an estimated 55 adults left."
The call comes amid fresh efforts by prominent New Zealanders to get more action on the issue.
Singer-songwriter Jamie McDell recently wrote and recorded a new track Son of the Ocean enlisting 55 young New Zealanders to join her on vocals, while freediver William Trubridge is also calling for better protection.