Morrison urges calm on $10 airport tax

Federal Treasurer Scott Morrison says any talk of slugging Sydney airport passengers with a tax of up to $10 to help pay for a second airport at Badgerys Creek is "premature".

The government is reportedly considering the proposal by former Treasurer Joe Hockey as it mulls over how it will pay for the multi-billion dollar project.

Mr Morrison says the government is talking with the Southern Cross Airports Corporation, the group that runs Sydney airport, and he doesn't want to prejudice the outcomes.