Gay, lesbian and bisexual rights organisation Stonewall is calling for the public to lobby the Government to ensure its civil partnership proposal becomes law in the UK.
The proposal outlines new rights for same-sex couples, which the organisation says will overturn the current "fundamental human dignities" denied them, such as property rights and being able to register their relationships.
Chief executive Ben Summerskill said: "We're encouraging as many people as possible to write to the Government by the 30 September deadline. Don't forget that all those who oppose equality so bitterly, such as the Christian Institute, will be writing in too."
Postcards are downloadable from the organisation's website, www.stonewall.org.uk, and must arrive by the end of this month.