LAHORE - Johannesburg, Dubai and Abu Dhabi are being considered as possible venues to host the Champions Trophy this year, a senior International Cricket Council (ICC) official said on Monday. The ICC executive board last month shifted the premier One-day tournament out of Pakistan with a possible boycott by five of the eight teams due to security concerns. Sri Lanka is the back-up venue but Dave Richardson, ICC general manager for cricket, said some doubts had been raised as September-October, when the event is planned, would be the monsoon season in the island nation. "Some doubts have been raised over Sri Lanka being a suitable venue more from a weather point of view," Richardson said Monday. "What is decided is that the CT has to be held in one place with at least two venues and completed in 12 days time so that narrows down the choice of other possible options," he said. Richardson said the possible options were the South African capital and Dubai and Abu Dhabi in the United Arab Emirates. "I think these options would be in the frame when the venue is finalised in March-April," he added. The tournament was postponed from last year before it was shifted out of Pakistan due to security issues. Reaction to international cricket's umpire referral system has been mixed, a top official was quioted by a wire agency. The International Cricket Council (ICC) last year introduced the trial system, under which teams can challenge three decisions made by field umpires during an innings -- which are then referred to the television umpire. The number of challenges was reduced to two in the ongoing West Indies-England and Australia-South Africa series -- but some decisions left teams confused. ICC general manager Dave Richardson said cricket is the most complicated game to umpire. "I think using technology has got a mixed reaction, there are people who think, yes we've got to go with the technology, and others say we should revert to the traditions and accept the umpires' decisions no matter what they are," Richardson told a news conference. He said he accepted some mistakes had been made. "This trial is all about trying to find a way of using technology that works because our previous trials raised questions and not all the answers were available," said Richardson, a former South African wicket-keeper. Richardson said the current trial also raised some issues. "I am grateful that some issues have been raised. First of all faint edges, if you don't have hot spot (technology) and even hot spot might not be able to tell you whether there's been a faint edge or not. Some people say what's the use of the technology if you can't get it 100 percent correct but my answer is we can never expect 100 percent correct decisions and if we get close to 98 per cent, it's an excellent result." Richardson said the response had been positive after the first two series -- between India and Sri Lanka and New Zealand-West Indies last year. "We had three positives... which proved that it could work without umpires being de-skilled in any way. We don't want the umpires just to become coat hangers or ball counters," said Richardson. "Secondly, the decisions have to be improved and what we found in the first two trials was that correct decision percent went up from about 93 to 98 percent. "At the end of the trial we can find that the decision making has improved." Richardson said the feedback will be brought before the ICC cricket committee. "We need to collect the data from the series in South Africa and then the Cricket Committee meets in May, chaired by Clive Lloyd (former West Indian captain) with people like Mark Taylor (former Australian captain) and umpire Simon Taufel, we will look at it."