"There are quite a number of countries who favour it, and there are some who have got concerns about it's reliability," ICC chief executive Haroon Lorgat said.
Hot Spot was shown to be dodgy during India's calamitous tour of England in the middle of this year, during which they lost all four tests, the only three of five ODIs to get a result, and the only T20 match.
Hot Spot is now off the list of basic requirements for the DRS, Lorgat describing that as recognition that it "was not as reliable as we would like it to be".
So the responsibility goes back to individual countries. Both must agree for it to be used in a series. The cost of the DRS is estimated to be about US$5000 ($6380) a day, according to the ICC, making it problematic for some countries to afford.
A central sponsor can only be obtained if there is unanimity among the test-playing nations.
* Plans for a test championship to start in 2013 look likely to be put back four years.
The tournament was to be held in England for the first time, with the final at Lord's.
Instead the ODI Champions Trophy is likely to remain on the calendar.
Broadcast partners ESPN reckoned swapping from 50-overs to a test championship could cost the ICC about US$3 million, which in turn would reduce the ICC's payments to member boards.