Exporters face delayed cargo shipments and higher freight charges if dockworkers at US Gulf and east coast ports take industrial action in the coming weeks over new labour contracts.

The disruption would come during the peak pre-Christmas and New Year shipping season as Hong Kong and mainland suppliers rush to help fill store shelves with toys, clothes, electronics and other consumables.

Charles de Trenck, the head of consultancy firm Transport Trackers, said any unrest would affect everyone.