World opinion opposes aggressive steps as a way of stopping a possible Iranian nuclear arms programme, according to a 25-nation poll for BBC World Service.
But only 17% of those polled believed Iranian assurances that research it is carrying out is just for energy needs.
The most popular course of action, with 39% support, was to use only diplomatic efforts; 11% favoured military strikes.
Last month, Iran failed to abide by a UN deadline to halt uranium enrichment which could lead to sanctions.
An average of 30% of respondents favoured economic sanctions if Iran continued to produce nuclear fuel.
The survey asked 27,407 people in countries ranging from the US and Great Britain to Brazil, Egypt, France, India, Indonesia, Israel, Nigeria, Poland, Russia and Turkey.
The survey, by the international polling organisation GlobeScan, has a margin of error of between plus-or-minus 2.5% and 4%.
Poll analyst Steven Kull, of the University of Maryland, said: "Clearly world opinion rejects Iran's claim that it is simply trying to develop nuclear energy.
"But at this point the world public favours addressing the problem through diplomacy rather than a confrontational approach."
Nearly three-quarters of respondents said they would be concerned if Iran were to develop nuclear weapons, with 43% saying they would be "very concerned".
In general, there appeared to be a world-wide mandate for stricter controls on the production of nuclear fuels which could be used in weapons.
Fifty-two percent favoured a new effort to have the UN develop new controls, while 33% favoured preserving the existing system allowing non-nuclear powers to develop nuclear fuel but not weapons.
The questionnaire also showed respondents in Egypt and Turkey had a strong sense of entitlement to have a nuclear capacity.
Only 29% in each country agreed the UN should stop countries from producing their own nuclear fuel, but provide them with the fuel they need.
A recent report by the UN's nuclear watchdog said Iran started a new round of uranium enrichment, which can be used to make weapons, just days before the UN deadline to halt it.
Tehran says it is completely within its rights to pursue a nuclear power programme and insists that is what it is doing.