The Lions have declined Australia's offer to host this summer's series against South Africa.
A board meeting on Friday made the decision due to the lack of financial certainty over the finance of Rugby Australia staging the eight-game tour, which culminates in a three-Test series against the Springboks.
Four options remain under consideration but each has significant drawbacks with a decision due this month.
Proceeding with the original itinerary in South Africa either with small crowds or behind closed doors could yet happen, while the financially-risky possibility of holding the tour in Britain and Ireland is also being explored.
Postponing it until next year is the least likely course of action due to the ramifications for the home unions' summer tours, while the last option is cancellation.
South Africa's board meet next week with the likelihood of the world champions hosting the Lions behind closed doors gaining momentum.
