Kell Brook has again taken aim at British rival Amir Khan by questioning the credibility of his fight with Terence Crawford.

Brook and Khan have long been in negotiations for a welterweight bout, with the latter suggesting in December that they were edging towards an agreement to settle a war of words in the ring.

But a deal has yet to be sealed and it was announced this week that Khan will instead face WBO champion Crawford in the United States on April 20.

And so, on Friday, Brook used the subsequent announcement of a clash between Saul 'Canelo' Alvarez and Daniel Jacobs to mock Khan.

"Nice to see a genuine boxing matchup being announced this week with TWO credible fighters," Brook wrote on Twitter, seemingly poking fun at Khan's fight.

Brook (38-2) last fought in December, defeating Michael Zerafa in Sheffield.