The Pope has arrived in Washington for his first official visit to the United States.

President George W. Bush greeted Pope Benedict XVI when the pontiff arrived at Andrews Air Force Base outside the US capital.

He was accompanied by first lady Laura Bush and his daughter Jenna along with several senior American Roman Catholic prelates.

During his flight from Rome, the Pope said he was determined to keep paedophiles out of the priesthood after child abuse scandals rocked the Church in the US.

The scandal of American priests sexually abusing youths broke in 2002 and has forced dioceses to pay out millions in damages to victims.

The Pope said: "We will absolutely exclude paedophiles from the sacred ministry.

"It is more important to have good priests than to have many priests," he said, adding the scandal had left him "deeply ashamed".

Polls say three-quarters of US Catholics approve of the pontiff, but just as many say they disapprove of the defensive way the Church initially responded to the sex abuse crisis.

The Pope also said he would discuss the issue of immigration from poor countries with Mr Bush, saying: "The United States has to help these countries develop.

"It is in the interest of everyone, not only these countries but of the world and particularly of the United States."

During the six-day trip, Pope Benedict will pray at Ground Zero, the site in New York where the World Trade Center was destroyed on September 11 2001, and address the United Nations.

© Independent Television News Limited 2008. All rights reserved.