Wearables giant Fitbit has confirmed it is buying the assets that power the smartwatches of rival firm Pebble, but not its existing devices.

The heavily rumoured deal does not include any of Pebble's products already on sale, which Pebble said would continue to function as normal.

But the manufacturer said work on the firm's upcoming Time 2, Core and Time Round products crowd-funded on Kickstarter were being halted, with refunds being offered to those who backed them, and all hardware operations ending.

Fitbit is the market leader in wearable technology, including fitness trackers, while Pebble first came to prominence via Kickstarter and its crowd-funded smartwatch in 2012, which raised more than $10 million.

It has been suggested Fitbit is looking to improve its own smartwatch offering after its first venture into the market - the Blaze - received a mixed reception when launched earlier this year.

Pebble said many of its "team and resources" were joining Fitbit as a result of the deal.

"Pebble's expertise, philosophy, and culture will live on at Fitbit," a company statement read.

"Much of our team and resources will join Fitbit to deliver new 'moments of awesome' in future Fitbit products, developer tools, and experiences.

"As our transition progresses, we'll have exciting new stories to tell and milestones to celebrate."

The announcement comes after Pebble cut 25% of its workforce earlier this year, and chief executive Eric Migicovsky said at the time that "money is pretty tight these days".

Reports claim Mr Migicovsky will not join Fitbit in wake of the deal.

Fitbit co-founder James Park said: "With basic wearables getting smarter and smartwatches adding health and fitness capabilities, we see an opportunity to build on our strengths and extend our leadership position in the wearables category.

"With this acquisition, we're well positioned to accelerate the expansion of our platform and ecosystem to make Fitbit a vital part of daily life for a wider set of consumers, as well as build the tools healthcare providers, insurers and employers need to more meaningfully integrate wearable technology into preventative and chronic care."