Pope Benedict XVI's announcement Monday that he will step down Feb. 28 due to his "advanced age" was received with surprise and respect around the world.

The German-born Benedict XVI, who turns 86 in two months and became pontiff on April 19, 2005, disclosed the decision during a meeting with cardinals.

Italy's outgoing prime minister, Mario Monti, said Monday that he felt "very disturbed" over the news of the pontiff's impending departure, while Italian President Giorgio Napolitano praised Benedict's "extraordinary courage" in making the announcement that he will resign because he lacks the strength to continue in the post.

Spain's King Juan Carlos on Monday acknowledged the hard work and dedication shown by Benedict during his pontificate, and he emphasized the "special relationship" the pope has maintained with the Iberian nation, as "reflected in the three memorable visits" he made to the country.

The monarch recalled that on those three visits to Spain the pope "held meetings with the Spanish Royal Family, dominated by affection and closeness."

German Chancellor Angela Merkel on Monday thanked Benedict XVI for his years of work at the helm of the Catholic Church and wished him the best after his resignation, a "difficult decision" that she said deserved "the greatest respect."

Merkel, a Protestant, also recalled the "pride" she felt when then-Cardinal Joseph Ratzinger was elected pope eight years ago.

The leader of the one of the world's most-populous Catholic nations, Mexican President Enrique Peña Nieto, expressed his "solidarity and respect" for Benedict's decision.

"On behalf of Americans everywhere, Michelle and I wish to extend our appreciation and prayers to His Holiness Pope Benedict XVI. Michelle and I warmly remember our meeting with the Holy Father in 2009, and I have appreciated our work together over these last four years," U.S. President Barack Obama said.

"The Church plays a critical role in the United States and the world, and I wish the best to those who will soon gather to choose His Holiness Pope Benedict XVI's successor," the president said in a statement. EFE