The Port of Halifax says it will hold CN Rail to a promise of on-time delivery for its shipping lines.

Representatives of the port authority met with three CN Rail executives Thursday to discuss the rail line's decision to cut its daily service from two trains to one.

The single train will be longer, stretching 3,400 metres.

"What we've been told is the key transit times to Chicago and Toronto haven't changed," said George Malec, vice-president of operations and business development for the port.

"What we as a port authority will do is closely scrutinize the daily operation of the service, and CN has committed to coming back to Halifax … and review the operation of the service to make sure it is in fact as advertised."

Malec said the port authority will monitor the waiting time for containers to get loaded onto the train.

CN Rail has said that a steady decline in container traffic at the port was the reason it dropped one of its daily train departures.

Container traffic was down 20 per cent during the first half of this year, compared with 2007.