New Zealand skipper Kane Williamson on Thursday said he will be back to full fitness after dealing with a hamstring and elbow injury ahead of the T20 World Cup.

Williamson missed the final league match of the IPL for Sunrisers Hyderabad with a hamstring niggle before joining his national side for T20's showpiece event starting Sunday.

The Kiwis play their opening game in the Super 12s stage of the 16-nation tournament on October 26 against Pakistan and Williamson believes there is enough time to recover.

"The hamstring is minor, it's progressing nicely, so not too many concerns and we've still got plenty of time," the 31-year-old Williamson said.

"So, yeah, hopefully in the next sort of few days or so, I'll be taking basically full part in the training. So, it's all good."

Williamson's elbow has also troubled him in the last few months with the star batsman forced to opt out of bilateral series and tournaments including The Hundred.

"The elbow - it has just been a bit of a slow-burner. Yeah, it has been quite frustrating for a long period of time," said Williamson.

"However, it has definitely improved a bit over the last two months I've had after the World Test Championship.

"In rehab, it has definitely seemed to move forward, which is refreshing, but still a little bit of time to get back to a 100 (per cent), but it's definitely better."

Williamson, who has scored over 15,000 international runs across the three formats, said he was having some discomfort while gripping the bat and extending the elbow.

"Basically just gripping and then extending," Williamson said.

"So, which you do a lot of obviously (while) batting and it has been frustrating certainly when it was at its worst. But the harder you grip and further you extend, the more it seems to be quite disruptive."

He added: "Like I said there's been a lot of improvement over the last three months, which is good...and it's nice to be able to focus a bit more on the cricketing side of things rather than having constant negotiations with physios."

The T20 World Cup kicks off with Oman -- joint hosts with the United Arab Emirates -- taking on Papua New Guinea in a first qualifier.

Top nations will join the event on October 23 with Australia and South Africa playing the opener of the Super 12 stage and England up against holders West Indies.