Scotland Secretary David Mundell comes out as gay
David Cameron's spokesman said the Prime Minister had been informed and was "delighted that he's in a position to take this step".
Mr Mundell's announcement means he is the first ever openly gay Conservative Cabinet minister.
Scotland's only Tory MP said he had been through "conflicting emotions" while deciding whether or not to come out, but that ultimately it has been a "positive and uplifting" experience.
"New Year, new start! I have already set out my political priorities for the year and now I am setting out my personal one. Having taken one of the most important decisions of my life and resolved to come out publicly as gay in 2016, I just want to get on with it, and now, just like that, I have said it. How can it be both so easy and so hard to say a few short words?" he wrote.
"Other than the intensely personal and positive difference it makes to me, and the way I can live my life, my hope is that my coming out doesn’t change anything else about how I go about my work or how people treat me," Mr Mundell added.
"Gender and sexuality should make no difference whether you are a Cabinet Minister or in any other walk of life and I hope that I can, in my own way, reinforce that message."