General Motors Europe told unions Thursday that it will close its Opel auto production plant in Antwerp, Belgium, with the loss of 2,300 jobs.

"They have announced to us their intention to proceed towards collective redundancy and the closure of the business," said Walter Cnop, of the CSC union's metalworkers' branch.

Opel confirmed in a statement that the site was expected to be closed this year.

Workers blocked access to the northern Belgian factory Wednesday ahead of planned talks at which they feared the axe would finally fall.

"It's an absolute catastrophe for Belgian workers and manufacturing," Cnop added, slamming management "arrogance" for a decision he said was "based on political considerations (and) in no way assessed on economic grounds."

A 24-hour blockade begun Wednesday representing unions' "armory" was expected to be extended, he said, adding that unions were set to discuss further responses.

GM said it would cut 8,300 jobs out of a total of more than 50,000 employees across Europe.