A defiant Chris Froome said Team Sky “is not finished yet by any means”, despite Sky’s decision to pull the plug at the end of next year on a sponsorship deal worth £30m a year.

The four-times Tour de France winner also pledged to do everything possible to keep the team together, regardless of scepticism within cycling that another deep-pocketed sponsor will quickly ride to the rescue of the richest team in the sport.

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“Everyone at Team Sky has big ambitions for 2019 and this news has made us more determined than ever to make them happen,” Froome wrote on Twitter. “I can’t predict the future but I can say this with absolute certainty, this is a really special team.

“We plan to be together in 2020 if at all possible and we will all be doing everything we can to help make that happen – in different colours with a new partner but the same values, focus and desire to win.”

The Team Sky principal, Sir Dave Brailsford, who is well connected in the corporate world, is confident that the combination of experienced hands such as Froome, a six-times grand tour winner, and the brilliant young Colombian Egan Bernal, who signed a new five-year contract in October, will be an attractive proposition for new sponsors. However, he accepts that there needs to be clarity before the Tour de France in July, as that is when the majority of teams do their business for the following season.

“You’ve got to stay positive but you’ve also got to be realistic, and there are certain timescales involved,” he admitted. “Either we move on as a team with a new partner, or there’ll come a timescale when that’s not going to be possible and people move on.”

However, any sponsor will also note that Froome will be 35 in May 2020, and Geraint Thomas 34, meaning the team are likely to be rebuilt around Bernal who, while a fantastic talent, is likely to be much less attractive to a British or European brand.

It is also likely other teams will sound out Team Sky riders early next year, which will only add to the uncertainty about how a rebranded team would line up in 2020. The news Sky will end its sponsorship, which was broken to stunned riders and staff over dinner at their training camp in Mallorca on Tuesday, draws to an end nearly a decade of success during which the team won six Tours de France as well as a Giro d’Italia and Vuelta a España – along with 52 other stage races and 25 one-day races.

Brailsford has paid tribute to his team, who began with the goal of getting a British rider to win the Tour de France for the first time – a target accomplished when Bradley Wiggins took the yellow jersey in 2012 – and said he was proud of their part in inspiring nearly two million people to cycle regularly.

“The vision for Team Sky began with the ambition to build a clean, winning team around a core of British riders and staff,” he said. “The team’s success has been the result of the talent, dedication and hard work of a remarkable group of people who have constantly challenged themselves to scale new heights of performance. None of this would have been possible without Sky. We are proud of the part we have played in Britain’s transformation into a cycling nation over the last decade.”

Sky executives are understood to have told a shocked Brailsford last week that with Comcast’s £30bn takeover of Sky in September, it was the natural time to end the partnership. They also strongly deny their decision – made by the chief executive Jeremy Darroch – was influenced by a number of controversies the team have faced, especially the damning report by the Digital Culture Media and Sport select committee in March which looked into the case of a Jiffy bag delivered to Wiggins in 2011.

Facebook Twitter Pinterest Team Sky’s principal, Sir Dave Brailsford. Photograph: Marco Bertorello/AFP/Getty Images

The DCMS report, in particular, created waves of negative headlines when it concluded Team Sky had cynically abused the anti-doping system by using therapeutic use exemption certificates to allow the administration of the performance-enhancing drug triamcinolone. It also concluded such practices were “inconsistent with their original aim of ‘winning clean’ and maintaining the highest ethical standards within their sport”.

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There was more bad publicity when it was revealed that Froome had an adverse analytical finding for salbutamol in 2017, although he was later cleared by cycling’s governing body, the UCI. More negative PR is also expected when Richard Freeman, the team’s former doctor, faces a GMC hearing on 6 February over an alleged delivery of testosterone to the national velodrome in Manchester in 2011.

In a statement Sky said it would now focus on other projects, such as its most recent flagship campaign, Sky Ocean Rescue, which aims to encourage businesses and the public to eliminate single-use plastic.