Gayle, who is set to retire from ODIs after the World Cup, is by far the most experienced player in West Indies' World Cup squad, with 10,151 runs in 289 ODIs. His career-best of 215, which came against Zimbabwe during the 2015 edition of the tournament, is still the highest ODI score for the team, and remains one of only eight double-centuries in the format.
"It is always an honour to represent the West Indies in any format and this World Cup for me is special," Gayle, who last captained West Indies in an ODI in June 2010, said after the announcement. "As a senior player, it is my responsibility to support the captain and everyone else in the team.
"This will probably be the biggest World Cup, so there will be great expectations and I know we will do very well for the people of the West Indies."
On his appointment as deputy for the tri-nation series, Hope said, "Ahead of this tournament I was asked to take on this role and I was happy to accept. Anything I'm asked to do for West Indies cricket I'm always happy and willing to put my hand up, so this is great."
The tri-nation series is set to end on May 17 in Malahide before West Indies make their way to England for the World Cup that begins a fortnight later. Their World Cup campaign begins with a trip to Trent Bridge to face Pakistan on May 31.