US President Barack Obama travelled home to Chicago to celebrate his 49th birthday today. But Michelle Obama went to Spain where her luxury hotel costs R47,500 a day

The White House says Obama is looking forward to having dinner with friends and spending the night at his house in the city’s Hyde  Park neighbourhood for his birthday today.

But First Lady Michelle Obama and her 9-year-old daughter Sasha arrived in Spain today for a "brief holiday".

A picture published on the websites of several Spanish newspapers showed her wearing sunglasses and carrying a large black bag, disembarking the US air force plane at Malaga airport in southern Spain with her daughter.

The pair were travelling by car to the five-star Hotel Villa Padierna near Marbella located some 40 kilometres away where they will stay for four days on what the White House has described as a "private mother-daughter holiday" with several long-time family friends.

The hotel's owner Ricardo Arranz told public radio RNE that the Obamas had reserved 60 rooms at the hotel for themselves, theirs friends and their extensive secret service detail.

"Everything is ready," he added.

Michelle and Barack's oldest daughter, 12-year-old Malia, is attending a summer camp in the United States.

Rates for a room start at the hotel start at 250 euros and rise to 5,000 euros (6,500 dollars, R47,500) for a villa with a 24-hour butler service and private pool and garden.

An Italian palazzo-style building about five kilometres rom the coast, the hotel has five restaurants, a spa and access to three 18-hole golf courses.

Meanwhile Barack Obama has not shied away from talking about his birthday, noting  that his hair is getting grayer and his metabolism is slowing down as another year passes.

Spokesman Robert Gibbs says that while there is no doubt that the presidency comes with enormous physical and mental strain, Obama "greatly enjoys" the job.

Obama also will attend Democratic fundraisers and tour an auto plant while in Chicago.