FRANKFURT (Reuters) - Restocking and a rush to fill up inventories ahead of the expiry of labour contracts at the end of September are supporting high transatlantic container shipments into the United States, the head of Germany's Hapag-Lloyd said in an online news briefing on Monday.

"There is some temptation by customers to bring in goods ahead of the labour contract expiry on September 30," said CEO Rolf Habben Jansen, who heads the world's fifth-biggest container liner.

"We see U.S. inventory levels getting back to normal, last year, they were down off the back of higher interest rates and they're now being built back up," he added, ruling out election-related manoeuvres by customers this year when specifically asked.

(Reporting by Vera Eckert, editing by Miranda Murray)