LUXEMBOURG, June 29 (Reuters) - European Union farm ministers failed to agree on Tuesday to approve six genetically modified (GM) maize varieties for import to the bloc, despite a warning that inaction could lead to a shortage of animal feed.

Following the deadlock, the import applications for use in food and feed can now be approved unilaterally by the bloc’s executive, the European Commission.

In principle that could happen “within a few weeks”, but the Commission has not yet decided whether the approval will be granted before or after the European summer break, a spokesman for the EU executive told Reuters.

Before the vote, EU Health and Consumer Commissioner John Dalli told ministers that authorisations should be approved as a priority to avoid any repeat of last year’s disruption to feed imports.

That was caused by the EU’s zero-tolerance policy on unapproved GM material in imports -- shipments of animal feed from the United States were refused entry to the bloc after minute traces of unapproved GM material were discovered in the cargo.

The Commission has said it will propose a small tolerance margin for unapproved GM in imports later this year to resolve the issue, but until then the only solution is for the EU to approve varieties individually for import. [ID:nLDE65922N]

One of the applications was to renew a previous EU approval for the insect-resistant Bt11 maize, developed by Swiss-based biotech company Syngenta SYNN.VX, which expired in 2007.

“A positive endorsement would effectively have signalled to key trading partners that the EU regulatory system for GMOs is functioning properly and would have helped to defuse mounting trade tensions,” said Syngenta spokesman Medard Schoenmaeckers.

“Syngenta is disappointed that once again, member states could not come to a decision.”

The other five covered new approvals for “stacked” maize varieties, developed by combining existing insect- and herbicide-resistant GM maize varieties together using conventional plant breeding techniques.

One was developed by Syngenta, two were developed jointly by subsidiaries of US chemicals companies DuPont DD.N and Dow Chemical DOW.N, and a further two were developed by Monsanto MON.N. (Reporting by Charlie Dunmore, editing by Anthony Barker)