* GM variety developed to withstand Monsanto weed-killer
* Impact "limited" due to small Canada market share -source (Adds S.Korea wheat importer comment, details, bullets)
SEOUL, June 18 (Reuters) - South Korea has suspended the sale of wheat and flour from Canada after the North American nation announced last week the discovery in mid-2017 of an unapproved genetically modified trait in Alberta province.
"We will only allow sale of wheat products that are confirmed not to contain unapproved genetically modified wheat," South Korea's Ministry of Food and Drug Safety said in a statement on Monday.
The Canadian Food Inspection Agency said on June 14 the grain containing a genetically modified trait, developed by Monsanto Co to tolerate its Roundup weed-killer, was found after it survived herbicide spraying.
Following the announcement of the GMO wheat discovery, Japan's farm ministry last week suspended its tenders and sales of wheat from Canada.
"The impact of suspending the sale of Canadian wheat and flour would be limited because the share of Canadian wheat imports is small," said a source from CJ Cheiljedang Corp , one of South Korea's major wheat importers and flour millers.
Canada is one of the world's largest wheat exporters and is South Korea's No.3 wheat supplier, after the United States and Australia.
In 2017, South Korea imported 226,355 tonnes of wheat from Canada, accounting for 9.2 percent of the country's total wheat imports, according to food ministry data.
As of June 15, South Korea had taken 89,683 tonnes of Canadian wheat for this year, making up 8.3 percent of the country's total wheat imports.
Reporting by Jane Chung; Editing by Kenneth Maxwell and Tom Hogue