A previously unscheduled visit to the Martin Luther King, Jr. Memorial in Washington, D.C. might be added to the papal schedule for Thursday morning, according to a source familiar with the White House.

"Pope Francis might stop by the Martin Luther King, Jr. Memorial Sept. 24, right before going to hold his speech before the two houses of Congress," the source told CNA.

The source also added that "at the moment, it is just an idea, and the organization is looking as if things might work out, as everything must be carefully organized in terms of traffic and security."

The Martin Luther King, Jr. Memorial is almost on the banks of the Potomac River, near the Franklin Delano Roosevelt Memorial; it was dedicated in 2011. The memorial is made up of a granite statue of King, and a wall inscribed with excerpts from his sermons and speeches.

According to the White House source, Pope Francis would spend some time in silent prayer before the statue, while en route from the apostolic nunciature on Massacchussetts Avenue, where he is staying, to Capitol Hill.

Pope Francis is expected to pass by Constitutional Avenue, already decorated with Vatican, American and D.C. flags.

The change of route, to accommodate the visit to the memorial, would take some 20 additional minutes, which means Pope Francis would leave the nunciature a little in advance, in order to be at the Capitol at 9.20 am sharp, as is already scheduled.

"This is just an opportunity, still under study," said the source. The main concern is obviously security, which has been tripled in D.C. for the Pope's arrival.

A visit to the MLK memorial would also have a political impact, with the Pope would underlining in this way the importance of civil rights.

A source familiar with Vatican diplomacy told CNA, "It would be a diplomatic move that would allude to the need for a civil uprise on themes like freedom (and especially religious freedom), without the Pope having to clearly mention the issue in his speech before the House of Representatives and the Senate."