(CNN) Britain's Prince Harry is pulling out all the stops for his upcoming guest editor slot -- complete with a chat with former US President Barack Obama.

The interview recorded at September's Invictus Games in Toronto will be broadcast on BBC Radio 4 on December 27.

In a teaser released Sunday, the pair's longtime bromance was on full display as they traded quips while Harry explained his editorial process.

"Do I need a British accent?" Obama interrupts, shooting a smirk at the prince.

Here is a sneak preview of when @BarackObama met Prince Harry for the interview. Listen to the full interview on 27th December on @BBCr4today. pic.twitter.com/p5I1dUdyhx — Kensington Palace (@KensingtonRoyal) December 17, 2017

Without missing a beat, Harry responds "not at all" before warning the former commander-in-chief that he'll get "the face" if there are any long pauses between answers.

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