Pope Benedict has landed in the U.S. His plane touched down outside of Washington, D.C., just after 4 p.m. EDT Tuesday, where he was greeted by U.S. President George Bush and his wife Laura Bush.

En route to the U.S. for his first American visit since being selected to lead the Catholic church, Benedict said he was "deeply ashamed" of the sexual abuse scandals that have rocked the Roman Catholic church in recent years.

"It is a great suffering for the church in the United States and for the church in general and for me personally that this could happen," Benedict said. "It is difficult for me to understand how it was possible that priests betray in this way their mission ... to these children."

Benedict was speaking to reporters on the special Alitalia plane carrying him from Rome to Washington to kick off his visit.

He vowed to exclude pedophiles from the ministry and pledged to work to ensure that such abuses aren't repeated.

Benedict, 81, was elected in 2005.

His visit will be filled with high profile events, including two masses at baseball stadiums, an address to the United Nations and a prayer stop at Ground Zero in New York.

His plane will touch down at Andrews Air Force Base on Tuesday afternoon, where he will be met on the tarmac by Bush himself. The presidential welcome will be the pope's only public appearance on the first day of his visit.

On Wednesday, Benedict will visit the White House for an official visit with Bush. About 12,000 followers are expected to gather for the event. Benedict is also scheduled to attend a prayer service with American bishops.

Father Thomas Rosica, CEO of Salt and Light Catholic Television Network, said it will be a visit filled with specific messages tailored for specific groups.

"In a world struggling for identity, struggling for truth, in a world filled with religious fanaticism we have a religious leader who's a teacher, someone who speaks of wisdom and truth and experience, who's going to let the world know we can't do it without God. It's as simple as that," Rosica told CTV's Canada AM.

He said the pope's visit to the United Nation will be set in the context of the 60th anniversary of the Declaration of Human Rights.

"He's going to address some great issues -- certainly of war and peace, dignity of the human person, of human rights, of freedom and of really taking a stand for truth," Rosica said.

The pope's visit comes as four major U.S. Catholic dioceses celebrate their bi-centenary anniversaries. Rosica said Benedict will speak to a gathering of priests about the state of the Catholic church, and will speak specifically about the sex scandal that broke in 2002.

Rosica said he expected it to be "a message of hope and encouragement and let's move forward beyond this crisis."

Bush and the pope don't agree on all major issues. Their opinions diverge on the Iraq war, capital punishment and strained U.S. relations with Cuba.

Benedict asked for support before leaving the Vatican, requesting during his Sunday address that followers pray that his visit would serve as a "time of spiritual renewal for Americans."

About 65 million of the world's one billion Catholics live in the U.S.

A poll released on the weekend by the Center for Applied Research in the Apostolate of Georgetown University found that eight in 10 Catholics are somewhat or very satisfied with Benedict's leadership so far.