The MoT test could be changed so that numberplates, which have been modified to evade speed cameras fail.
Under the Department for Transport's proposals, a vehicle will fail if traffic enforcement cameras cannot read the characters on the 'plate.
The test already includes a basic check of numberplates to see if characters are properly formed and recognisable, and the 'plates are complete and not in danger of falling off.
The cost of the standard test will also rise by 90p to 54.
Both changes are intended to take effect in April 2009, pending a consultation process that will be completed by the end of February.