And a palace source told NBC News on Tuesday: "They are not commenting on individual guests being invited or not, but president and Mrs. Obama will not be attending the wedding. But the couples look forward to seeing each other soon."
Several outlets, including The Telegraph, reported that May isn't on the list either.
Some 260 government officials from around the world attended Prince William's wedding to Kate Middleton, in 2011, but it seems the May 19 ceremony uniting his brother Prince Harry and Markle is going to be a much smaller affair.
President Obama did not attend Prince William's wedding, but leaders from commonwealth countries including Australia and New Zealand were on the guest list.
There had been speculation about whether President Obama would be invited since he is close to Prince Harry. The groom-to-be interviewed President Obama on the BBC's Radio 4 "Today" program last year and was asked by a BBC reporter whether the former leader would be on the guest list.
The prince responded: "Well, I don't know about that. We haven't put the invites or the guest list together yet so who knows whether he's going to be invited or not. I wouldn't want to ruin that surprise."
But an invitation to President Obama would have created a political problem for the British government if the couple had snubbed President Trump — who has yet to make an official visit to the United Kingdom.
The couple is not holding a state wedding, since Prince Harry is currently fifth in line to the throne following his father Prince Charles, his brother Prince William and Prince William's two children.
The couple is also inviting members of the public who have performed a service to their community or who have demonstrated bravery to watch in the grounds of the church.
The royal wedding will take place at St. George's Chapel, in the town of Windsor outside London. The chapel seats 600 people. The couple have said they don't want gifts but have asked for charitable donations instead.
Markle, who has been an actress on the USA Network show, "Suits," is inviting some of her former castmates and the executive producer of the USA Network series, Aaron Korsh, according to a person familiar with the invitation list. Invited guests were asked to be discreet, the person said.
USA Networks is owned by NBC Universal, the parent company of NBC News.