(Adds Bayer and Anvisa comments, detail on abamectin and thiram)
BRASÍLIA, Sept 3 (Reuters) - A Brazilian court on Monday overturned an injunction banning products containing the popular weed-killer glyphosate, knocking down a previous ruling that had been set to disrupt the soy planting season set to begin this month.
A Brazilian judge ruled last month to halt the registration of new glyphosate-based products in the country and to suspend existing registrations after 30 days, until health agency Anvisa issues a pending ruling on its safety.
That 30-day deadline had been due to pass on Monday, just as the first month of soy planting gets under way. The injunction and the subsequent reversal also applied to insecticide abamectin and fungicide thiram.
Judge Kássio Marques, of the regional federal court of the first district in Brasilia, based the ruling suspending the injunction on the government's argument that banning glyphosate and the other two agrochemicals could harm the country's economy.
Marques said in the decision "nothing justifies the suspension and abrupt removal of registrations of products containing glyphosate, abamectin and thiram as active ingredients without an analysis of the serious impacts on the country's economy and population in general."
Brazil is the world's largest exporter of soybeans and relies heavily on the agrochemical, with Bayer AG's Monsanto SA the biggest seller of glyphosate products in the country.
"This ruling is very good news for Brazilian growers, who count on glyphosate-based herbicides to control weeds and grow their crops safely and effectively," Bayer crop science chief Liam Condon said in a statement.
Anvisa, which has been reviewing glyphosate's safety since 2008 without issuing a decision, said it was aware of Monday's ruling and would take the necessary legal and technical steps in response.
Federal prosecutors brought the lawsuit to pressure Anvisa to make a decision, saying glyphosate and the other chemicals deserved to be reevaluated based on new evidence that has come to light on their safety. The prosecutor's office did not immediately respond to request for comment on Monday's ruling.
Hundreds of lawsuits alleging Monsanto's glyphosate products cause cancer are making their way through U.S. courts. A 2015 study conducted by an arm of the World Health Organization classified glyphosate as probably carcinogenic to humans.
Bayer and Monsanto say decades of use and numerous reviews of glyphosate show the chemical to be safe. (Reporting by Ricado Brito, Ana Mano and Jake Spring Additional reporting by Frankfurt newsroom Editing by Andrea Ricci, James Dalgleish and Frances Kerry)