FIFA's ruling Council had been expected to decide in Miami this week whether to introduce the tournament, but the task force's report, which has been seen by Reuters, concluded that a vote should not take place.
The decision is the latest blow to FIFA president Gianni Infantino's hopes of quickly bringing in new revenue streams through additional competitions.
The FIFA Council will, however, vote on Friday on whether to hold a 'pilot' edition of a 24-team Club World Cup in 2021.
That plan is opposed by European soccer body UEFA and Europe's professional leagues, who do not want to start any new competition until 2025 at the earliest.
Infantino's plans for the two new tournaments were first put forward at a FIFA meeting in Bogota over a year ago and were based on an offer from a consortium willing to invest $25 billion (AU$35 billion) over a 12-year cycle in return for a 49 percent stake in the competitions.
The potential investors were not named publicly by Infantino, who cited a non-disclosure agreement. FIFA suggested earlier this month that other bids would also be invited once it had decided on the competition format.
The task force said they had looked at various models for a Nations League competition, which is based on UEFA's new tournament.
The original idea was for a worldwide qualifying system, based on regional confederations, with a 'Final Eight' tournament every two years to find the winner.
Yet after consulting with FA's and regional confederations, the task force was unable to find agreement on a structure and also hit problems with those bodies' existing commercial contracts, the report said.
Instead of putting a plan to a vote in Miami on Friday, the report said the task force had concluded that more work needed to be done in the next few months "before it will be able to come to conclusions and potentially make concrete proposals to the FIFA Council."
A vote, however, will be held on the plans to overhaul the Club World Cup from its current annual, seven-team event.
The task force will ask FIFA's Council to organise a pilot of a revamped Club World Cup with 24 teams in 2021 in the slot reserved on the international match calendar for the Confederations Cup.
The plan has already won the backing of the German FA although global players union FIFPro has expressed opposition.
The Council meeting will also discuss plans for expanding the 2022 World Cup in Qatar to 48 teams with possible additional hosts.
