Spain's Queen Letizia spent her birthday with President Barack Obama and his wife Michelle on Tuesday (15.09.15).

Queen Letizia

Queen Letizia

The 43-year-old royal celebrated the milestone by touring the White House in Washington, DC with her husband King Felipe VI, the First Lady and the head of state.

Letizia wandered around the residence and principal workplace of the President in a black and white figure-hugging floral dress, a crisp white blazer and killer heels.

She kicked off the day at Mount Vernon - the home of the George Washington - where she laid a wreath to honour the first US president, who passed away in 1799.

Letizia and Felipe also stopped by the residential neighbourhood Capitol Hill where the pair of them met lawmakers, according to HELLO! magazine.

Meanwhile, it's been a tough year for the brunette beauty so far as her grandfather sadly passed away two months ago.

Francisco Rocasolano, 98, tragically died in hospital in Salamanca, Spain in July due to coronary problems.

Queen Letizia was forced to cancel her arrangements to assist the National Fashion Awards ceremony at the Museo Del Traje in Madrid at the time in order to be with her family.