Officials have recently asked two importers to re-export the infested corn and soymeal delivered to Ho Chi Minh City port, Nguyen Xuan Hong, head of Vietnam's Plant Protection Department, was quoted by the radio's evening news bulletin as saying.
"We have warned that between now and the year end if five more cargoes are found with the violation, we will propose the Agriculture Ministry not to allow the import of India's corn and soymeal, the items often found with infestation," Hong was quoted as saying.
Several Vietnamese importers have switched to other origins to avoid the problem, the radio said.
India, a key corn supplier to Southeast Asian, exports around 300,000 tonnes of corn and up to 800,000 tonnes of soymeal each year to Vietnam.
In early 2011 the Vietnamese authorities rejected around 50,000 tonnes of Indian corn and soymeal after they found the same type of beetle, common in India, in the cargoes. Trading was disrupted until March 2011, when Vietnam resumed the import.
Soymeal is hardly infected by the beetle but the feed ingredient still suffers because it is carried together with infected corn.
Vietnam has rejected several cargoes of Indian corn and soymeal so far this year due to the same problem, traders said.
India, Argentina, the United States, Thailand and China top the list of feed and feed ingredient exporters to Vietnam.