Police said two trucks collided at the on ramp of the Southbound checking station at about 3.45pm today.

"It is a minor accident and police are there for traffic control," a police spokesperson said.

"They have blocked the road going into the checking station, but the Southbound lane of the Hume Highway is open and unaffected by this."

An RFS spokesperson said two trucks had been sent to the site to possibly control a small diesel spill.