The foursome met privately at Kensington Palace for afternoon tea and "discussed their shared interest in combatting the illegal wildlife trade," a spokesperson tells Us Weekly.
Pitt and Jolie's children did not accompany them on their trip overseas; however, Prince George tagged along with his parents to the meeting, Us reports.
"Brad and Angelina spent much longer with the Duke and Duchess than planned," a source told Us. "They ended up staying for almost a few hours."
Jolie, who is involved in U.K. foreign policy, is scheduled to have lunch at the Foreign & Commonwealth Office on Monday.
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