Prince Charles and Prince William are said to be eager to let the couple know they are welcome to return to the UK from Canada without having to resume their official royal duties.
A source said: “The palace is very worried about the Sussexes, because they are vulnerable outside the embrace of the family.
“They are making contingency plans in case the Sussexes suddenly turn round and say: ‘Can we come back under your wing?’”
The source added: "This is a looking ahead thing. There’s no timeline here. But everybody agrees that this is a fragile couple. Nobody is going to say, no they can’t come back."
As concern rises for the couple as they embark on their new life in Canada, William and Charles are doing everything they can to ensure the Sussexes know they are there for them.
“You see the way it has disintegrated over there in the last few days," a source told the publication.
“What is happening is that they are being told that there is love and affection on standby.”
The source added: “They are trying to rebuild the relationship between Charles and Harry and indeed between William and Harry.
“They are phoning him and trying to talk to him and extending a friendly hand.”