The holders are among the favourite to triumph in the UEFA showcase tournament, but Real Madrid star Alonso believes it will be very difficult to go all the way in Poland and Ukraine.

"The expectations aren't just high, but they are soaring. The bar is almost insurmountable," Alonso was quoted as saying by El Mundo Deportivo.

"The expectation can weigh you down a bit, but let's just hope this won't happen.

"Winning the title is going to be much more difficult this time than previously. However, our objective is obviously to successfully defend our title."

Spain start their Euro 2012 campaign with a Group C match against Italy on June 10, before taking on the Republic of Ireland four days later, and Croatia on June 18.