London: Bangladesh captain Mashrafe Mortaza accepted England were a far better side than the one his team knocked out of the 2015 World Cup but insisted the Tigers had improved too ahead of their Champions Trophy opener.

Tournament hosts England and Bangladesh launch the Champions Trophy, a 'mini World Cup' featuring cricket's leading eight one-day international sides, at the Oval on Thursday.

Both teams are set to feature several survivors from Bangladesh's 15-run win at Adelaide which condemned England to a woeful first-round exit from the last World Cup.

It was a result that led England to completely revamp their approach to the white-ball game.

But it was also an indication of how Bangladesh were more than just a team to be respected in sub-continental conditions, something they emphasised with wins over New Zealand and Ireland in a triangular warm-up tournament in Dublin this month.

"We just recently beat New Zealand in Ireland," Mortaza told reporters at the Oval on Wednesday.

It was some encouragement for Bangladesh after a 2016/17 tour of New Zealand where they were beaten in all formats.

"We couldn't win any matches, but the thing is, we played really good cricket," said Mortaza. "It's just we couldn't finish well, that's it."

Mortaza, also Bangladesh's captain in Adelaide, played down the significance of that result by telling reporters at the Oval on Wednesday: "Look, it was a long time back. And after then, England is a totally different team. The way they are playing, if you look at the last two years, their performance, they win almost everything. And especially at home, they are a serious side."

However, Mortaza added: "But we know that we are also a better side; that we are a very improving side.

"We have some experience. If you look at our side, at least four or five players have been playing cricket together the last 10, 12 years, more than 10, 12 years. That is the most important thing.

"The other thing also, is that we have some exciting youngsters like Mustafizur and Sabbir Rahman, Taskin Ahmed, those players are also in our side."

Bangladesh were shot out for 84 by Champions Trophy title-holders India at the Oval on Tuesday in a crushing warm-up defeat.

"You know, 84 obviously doesn't look good," said Mortaza. "I hope that the batters will understand their role and not to think about much about yesterday (Tuesday).

"I think we can handle tomorrow (Thursday) especially."