President Barack Obama and First Lady Michelle Obama were treated to a royal welcome at Buckingham Palace Tuesday.

London is the second stop on the Obama's four-nation European tour. The couple were received by William and Kate, The Duke and Duchess of Cambridge. The Obamas were not invited to the royal wedding (the high cost of providing security for the Obamas was reportedly one of the reasons why), so this was their first meeting with the newlyweds.

All eyes were on Michelle and Kate, two of the most stylish and watched women in the world. Check out the photos below:


The First Lady wore a pale green, floral dress Barbara Tfank's 2011 resort collection. The A-line silhouette is one she often favors. A metallic pink cropped jacket added a pop of color, and silvery pointed heels a modern touch.

The Duchess wore the "Shola" sheath dress by Reiss. The beige color complimented her tan (she and William just returned from their ten-day tropical honeymoon in the Seychelles). A gold necklace, simple clutch from Anya Hindmarch's Bespoke Collection and of course, that amazing sapphire engagement ring completed her look.

Of course, Reiss' website was inundated and shut down, much like how Libellula's was when designer Sophie Cranston was rumored to be the royal wedding dressmaker (it turned out to be McQueen's Sarah Burton).

So who won this clash of the style titans? Kate gets our vote for her effortlessly simple look. The First Lady looked a touch conservative (appropriate for a state visit) but still glamorous. Who looked better? Sound off in the comments below.