This is GB "country definitive" stamp for England showing a Tudor rose. Stamps in this design (and three others with three lions, a crownded lion with an English shield, and an oak tree) were first issued in 2001. This £1.10 value was issued on 29th March this year.
There are similar small format issues for Northern Ireland, Scotland and Wales which have had similar stamps since 1958. These were originaly called "regional" stamps but you can imagine how much this annoyed some people in these countries! Stanley Gibbons still calls them "Regional Issues"
