Some British officials fear a backlash from President Donald Trump amid rumors that Prince Harry may invite Barack Obama to his and fiancée Meghan Markle's wedding on May 19.

A senior government source told The Sun that the 33-year-old Prince made it clear that he wants the Obamas at the wedding, which officials fear could be seen as a snub to Trump and could jeopardize British and U.S. relations.

"Trump could react very badly if the Obamas get to a Royal wedding before he has had a chance to meet the Queen," the source said.

Prince Harry and Obama have been nurturing a friendship since the day they met at the Oval Office in October 2015, the Express noted, and it is expected that the former president and his wife, Michelle, would receive an invitation to the royal wedding.

However, senior officials are nervous that this could offend Trump, who has not received an invitation, and could make it difficult for British Prime Minister Theresa May to engage with the U.S. president, the Daily Mail said.

There are already tensions between the two countries, with threats of mass protests if Trump visits the U.K. to officially open the new U.S. embassy. A royal wedding snub could add to tensions, officials believe.

"Conversations are ongoing about and ministers will eventually have to decide," the government source told The Sun about Obama's invite. "If the PM lays down the law, Harry will just have to suck it up."

The wedding is not a state occasion so government only plays a consultative role in its planning, The Sun noted, while Buckingham Palace has full liberty of drawing up the guest list.