"He's progressed nicely and will be available, which is great news. He's very much looking forward to that," said Williamson.
By Niall Anderson in Cardiff
The Black Caps are set to be without Tim Southee for their World Cup opener against Sri Lanka.
The experienced seamer missed the Black Caps' final training with a right calf injury, and is unlikely to be able to take the new ball in Cardiff tonight.
Southee had impressed against India in the Black Caps' first warm-up game, and bowled during their first training upon reaching Cardiff, but picked up a knock during that session and didn't bowl in the nets during their final hitout.
His misfortune is set to hand an opportunity to Matt Henry, who was initially tipped to be carrying the drinks after undergoing a tight battle with Southee this summer for the second opening bowling spot alongside Trent Boult.
Southee's experience – and Henry conceding 107 runs in nine overs to the West Indies in a warm-up in Bristol – had perhaps given Southee the inside running, but with not much to separate the pair, risking Southee at this stage of the tournament is probably unnecessary.
A doubt also remains over who will be taking the reins at the opposite end of the order. Henry Nicholls is expected to open the batting alongside Martin Guptill, but has re-aggravated a left hamstring injury that had earlier sidelined him during the New Zealand XI series against Australia.
Nicholls had no noticeable strapping on his hamstring, but didn't bat during training. Colin Munro – who has also been battling a bruised foot - would be a straight swap at the top of the order if Nicholls is ruled out.
In more assuring news for the Black Caps, wicketkeeper Tom Latham was given a clean bill of health and is set to take his spot at number five in the batting order.
Provided he has no pre-match complications, captain Kane Williamson confirmed Latham was fit and available to play after recovering from his fractured finger.