The Victorian Electoral Commission has stopped a Liberal Party member in the highly marginal seat of Richmond handing out unregistered election pamphlets.

The VEC's Mike Lagastes told The Age that the candidate, Kevin Quoc Tran, who is a Liberal Party member but not an endorsed candidate, was "handing out material that was not registered".

Once the commission was aware of this, the election manager ordered Mr Tran to stop distributing the material, Mr Lagastes said.

"As soon as that happened, Kevin instructed his volunteers to cease handing out that material straight away."