Three Swedish environmental groups joined the Saami Council, which defends the rights of the reindeer-herding people from Norway to Russia, in opposing the Gates-funded project to release chalk dust from a balloon 12 miles up in the atmosphere to block solar radiation.

The first stratospheric test of geoengineering research technology, funded by Bill Gates, has been suspended under pressure from the indigenous people over whose heads it would take place, the Saami of northern Scandinavia. It may be moved back to the United States.

At the recommendation of the project’s Advisory Committee, the scheduled June test has been called off. That became public March 31.

When Bill Gates’ $4.5 million investment in geoengineering research came to light in 2010, one of the scientists he put in charge of the project, Ken Caldeira, said the money was not funding any field experiments. But as the project has grown and moved to Harvard, that line was crossed.