England qualified for the World Twenty20 semi-finals and knocked holders Sri Lanka out after a nailbiting 10-run victory in their do-or-die showdown in New Delhi on Saturday.

Jos Buttler smashed 66 in a 37-ball knock as England posted a commanding total of 171 for four that ultimately proved too much for Sri Lanka despite a brave, undefeated innings of 73 by injured skipper Angelo Mathews.

England are now likely to face New Zealand in a semi-final encounter in New Delhi on Wednesday having also defeated South Africa and Afghanistan in the group stages.

After the West Indies also qualified for the last four from Group 1 on Friday, Sri Lanka have no chance of progressing further although they do have one final match against South Africa.

Buttler, who hit eight four and two sixes, shared in a fourth-wicket partnership of 74 with skipper Eoin Morgan (22) as Sri Lanka's bowlers struggled to contain a late England onslaught at the Feroz Shah Kotla stadium.

But after having Sri Lanka on the ropes at 15 for four, they were then made to sweat for their victory with Mathews hammering England's spin bowlers to all corners despite struggling with a leg injury.

Mathews hit five sixes and three boundaries in a 54-ball innings that had England's fans with their hearts in their mouths.

He received crucial support from Chamara Kapugedera who hit 30 while Thisara Perera (20) and Dasun Shanaka who struck 15 off nine balls to take the contest down to the wire.

Moeen Ali and Adil Rashid were on the receiving off some fiercesome hitting from the Sri Lankans, with both men conceding 21 in a single over.

But Joe Root's stunning catch at mid-off to dismiss Shanaka off the bowling of Chris Jordan in the 19th over proved crucial as Mathews then began running out of partners.

With Sri Lanka needing 15 from the last six balls, allrounder Ben Stokes conceded just four runs to clinch the England victory.

Sri Lanka eventually made 161 for eight in their 20 overs.

England's innings got off to a poor start when Alex Hales, back in the team after a back injury, was given out lbw off the bowling of the veteran Rangana Herath with only four on the board.

Rookie spinner Jeffrey Vandersay was the pick of the Sri Lankan bowlers, taking two for 26 in an economical four-over spell in which he took the wickets of both Jason Roy and Root.

But powerful hitting from Roy, who made 42 off 39, and Root (25) began to turn the match in England's favour before Buttler then stepped on the accelerator.

Stokes finished the England innings off with a six before then starring with the ball.

He was the pick of the England bowlers, conceding just 19 runs in his four overs. Liam Plunkett also impressed with figures of one for 23.