PARIS: Euronext wheat extended gains in a shortened pre-Christmas session on Thursday, touching a near four-week high as concern over disruption to Argentine exports due to a labour strike continued to support grain markets. March milling wheat on the Paris-based Euronext exchange settled up 0.50 euros, or 0.2%, at 211.75 euros ($258.10) a tonne.

The contract rose as high as 212.00 euros, reaching the highest since Nov. 27 for the second session in a row. Chicago wheat also edged higher to trade close to a two-month peak.

A two-week-old strike by oilseed industry workers and grain inspectors in Argentina has stalled grain exports from the major agricultural supplier. The disruption has fuelled worries about soy supply from South America amid dry crop conditions that have created uncertainty about harvest prospects.