The word banquet is not usually used in this way. If you read the report, President Hu made a speech at the welcome dinner of the Shanghai World Expo, which was the welcome dinner.
China 20 10 Shanghai World Expo Welcome Dinner
"Welcome to XXXX delegation dinner" is not usually said this way, but it is the same when translated into English.
Welcome to the dinner of the Philippine agricultural delegation. "I think it's ok."