After initial X-rays were "reassuring," a follow-up CT scan showed that President-elect Joe Biden has hairline fractures in his foot following a fall this weekend, his doctor said.

Biden will likely need to wear a walking boot "for several weeks," Dr. Kevin O’Connor, the director of executive medicine at GW Medical Faculty Associates, said in a statement.

“Initial X-rays did not show any obvious fracture, but his clinical exam warranted more detailed imaging," O'Connor said in a statement. "Follow-up CT scan confirmed hairline (small) fractures of President-elect Biden’s lateral and intermediate cuneiform bones, which are in the mid-foot."

Biden fell over the weekend while playing with his dog.

President-elect Joe Biden suffered a sprained foot Saturday after slipping while playing with his dog, according to his doctor.

"Initial X-rays are reassuring that there is no obvious fracture and he will be getting an additional CT for more detailed imaging," Dr. Kevin O’Connor said in a statement Sunday following the examination at the Delaware Imaging Network facility at the Omega Professional Center in Newark.

Biden slipped while playing with his dog, Major, and twisted his ankle.

Biden and Vice President-elect Kamala Harris announced on Sunday seven top members of the White House senior communications staff, all of whom are female.

Jen Psaki, who served as communications director during the Obama administration and has been working as a spokeswoman for the transition, will be the White House press secretary

Kate Bedingfield, who served as the Biden campaign's communications director, will assume the same title in the White House.

Karine Jean-Pierre, who was a senior advisor to Biden's campaign, will serve as the principal deputy press secretary.

Pili Tobar, who was the Biden campaign's communications director for coalitions, will be the deputy White House communications director.

Other hires announced Sunday include Symone Sanders, a senior campaign adviser, who will be the chief spokeswoman for Harris, Ashley Etienne who will be Harris' communications director, and Elizabeth Alexander, who will be first lady Jill Biden's communications director.

-ABC News' John Verhovek

Biden slipped while playing with his dog Major, and twisted his ankle on Saturday. Out of an abundance of caution, he will be examined this afternoon by an orthopedist.

-ABC News' John Verhovek

Retired Navy Adm. William McRaven said Sunday that he doesn't think the president-elect can get back into the Iran nuclear deal without some changes.

"There's been a lot of controversy and a lot of folks who don't like the JCPOA and I understand that," McRaven said on ABC's "This Week." "But the fact of the matter is the JCPOA, which probably going to give us, you know, 10 to 12 to 15 years before the Iranians could possibly have enriched enough uranium to build bomb."

Complicating matters is Friday's apparent assassination of one of Iran's most prominent scientists, Mohsen Fakhrizadeh. While no one has claimed responsibility for the killing, the incident has brought out a full response from Iran's top officials, including the country's foreign minister, Mohammad Javad Zarif, who pointed the finger at Israel.

"Now, of course, by attacking their nuclear scientist, by really escalating this effort, the Iranians I think are going to be more compelled to try to get a bomb quicker. This is going to complicate President Biden's efforts, diplomatic efforts," he told "This Week" Co-anchor Martha Raddatz on Sunday. "Now, again, from the Iranian standpoint, after President Trump pulled out of the JCPOA, I think they are going to be very, very reluctant to get into any agreements with the United States at this point. So, a President Biden will have a difficult challenge on his hand."