The government has begun a three-month consultation on the introduction of national identity cards to airside workers, including pilots.
The government was previously expected to issue cards to airside workers at the beginning of next year, but unions, including the pilots' union Balpa, have threatened legal action over the issue.
The government's consultation will be seen by many as an attempt to water down opposition to the introduction of the national ID cards for airport workers.
Those working at airports are already vetted and carry ID cards. Unions are angry that their members will be forced to carry a national ID card, when every other citizen will have a choice as to whether to carry one when the scheme is fully rolled out in 2012.
The Identity and Passport Service (IPS) has invited comment on secondary legislation covering the airside card roll-out, now planned for the end of 2009.
Draft legislation is expected in the spring of next year, said the IPS.
The first National Identity Scheme cards will be issued to non-EEA (European Economic Area) foreign nationals from today. Around 40,000 such cards are expected to be in circulation by April 2009.