A transport truck carrying relief items for victims of the deadly tornadoes in Moore Oklahoma, has been given the approval to cross into the United States.

The 52-foot long truck carrying the goods was stopped at customs after crossing the Ambassador Bridge Wednesday night.

It was carrying 20,000 kilograms of goods, including diapers, blankets, food and locally grown produce.

"We had all the items we wanted to ship listed with the proper documentation for the border. We couldn't figure out why we were being detained," says Pastor Howard Mulder of Windsor Lifeline Outreach.

A U.S. customs broker says because President Barack Obama didn't declare Moore a 'disaster area,' the shipment is seen as commercial.

Therefore, all items must be listed with proper documentation and country of origin.

Organizers say it would have been impossible to complete before the food spoils.

"I was extremely frustrated after doing what we thought was a good deed the effort that went into it, even though it was just for three days there was a lot of labour involved," says Mulder.