Samsung's new smartphone debuts in London

South Korea's Samsung Electronics has unveiled a faster and larger version of its flagship smartphone as it seeks to cement its position as the world's best-selling mobile phone maker.

The Galaxy S3, introduced in London on Thursday, offers face-recognition technology, improved voice-activated controls and a more powerful processor that lets users watch video and write emails simultaneously.

The 4.8-inch (12.2-cm) screen is 22 percent larger than the Galaxy S2, its hugely popular predecessor. But Samsung says the phone is not much wider than the S2 due to a smaller frame.

Samsung shipped 44.5 million smartphones in the first quarter, exceeding the 35.1 million of US rival Apple, according to figures from market researcher Strategy Analytics last week.

It said the Korean firm also overtook Nokia as the biggest maker of all types of mobile phone.

Samsung is now pinning its hopes on the S3 to further erode its rivals' market share before an expected new version of Apple's iPhone this year.

Samsung, the world's largest technology firm in revenue terms, reported a record net profit of 5.05 trillion won ($4.44 billion) in the first quarter, thanks mainly to strong smartphone sales.

But it faces growing competition not just from Apple but also from Chinese makers offering cheaper products such as Huawei Technologies and ZTE Corp.

J.K. Shin, president of Samsung's mobile business, said the company aims to sell more than 200 million smartphones this year.

In an interview with Dow Jones Newswires, he said the company plans to offer more sub-$150 smartphones and introduce one using Microsoft's newest operating system in September.

The S3 will hit stores first in Europe, at the end of this month.

Shin said it includes software and design modifications that will not attract patent lawsuits.

"Features that were identified in previous lawsuits aren't in this new model. We've created and invented many technologies," he said.

Apple and Samsung are embroiled in legal disputes over patents in several countries. A US court has ordered their chief executives to hold settlement talks on May 21 and 22.

The Galaxy S3 runs on Google's Android software but with a faster chip.

Among other new features, it can detect eye movements and override the automatic shutdown if the user is looking at the screen.

"The S3 is an evolution but not a revolution," said Neil Mawston, executive director at Strategy Analytics. "It's an improvement but it's not a game changer nor an iPhone killer.

"Samsung's strategy is to offer good hardware at a cheaper price so it'll give Apple some pause for thought. It could put some pressure on Apple to develop a vastly improved iPhone 5."

-- Dow Jones Newswires contributed to this report --