Nike is expected to be offered the opportunity to take over as an IAAF sponsor after it was revealed that rival sportswear giant adidas wants to end its deal four years early.

Adidas is in talks with athletics' world governing body to pull the plug on its sponsorship in the wake of the doping scandal which has rocked the sport. However the IAAF's other sponsors are so far standing by the organisation including Canon which said it had no plans to seek an early exit from its deal.

Sources have confirmed that adidas' lawyers are looking to end the deal but IAAF insiders insist that it will not mean a major financial blow for the organisation.

The IAAF may not suffer financially as its sold the rights to Japanese-based marketing agency Dentsu which then sold them on to adidas in 2008. The prospect of Nike being tempted to replace adidas also looks possible, especially given the 38-year relationship between the company and IAAF president Lord Coe, who took over from Lamine Diack in August.

Adidas' move follows two damning reports by the World Anti-Doping Agency's (WADA) independent commission which revealed "state-sponsored'' doping in Russia and raised questions about widespread doping in other countries.

The IAAF said in a statement: "The IAAF is in close contact with all its sponsors and partners as we embark on our reform process.''

Adidas' action is in contrast to its position with world football's governing body, FIFA, where it did not join with the other major sponsors in demanding reforms and for Sepp Blatter to quit as president.

The IAAF deal was signed in 2008 and was reported at the time to be 33million US dollars (£23m). The BBC has reported that taking into account the 'value in kind' part of the agreement for kit and equipment the value could be as high as £5.6million a year.

Adidas has in recent years tried to position itself as being firmly anti-doping - some observers say as a deliberate tactic to point the finger at its main rivals Nike, who sponsor high-profile athletes who have served doping bans such as sprinter Justin Gatlin.

Tyson Gay was dropped by adidas when he tested positive for a banned substance in 2013.

Coe, who succeeded the since-disgraced Diack in the role in August last year, was a paid Nike ambassador for many years - including with his own parking place at its Oregon headquarters - until he announced in November he was severing links from the company after criticism about possible conflicts of interest.

Diack's son Papa Massata Diack - currently wanted by Interpol over the scandal which saw Russian athletes blackmailed into paying money to cover up positive drugs findings - is understood to have been involved with the adidas sponsorship deal via Dentsu. As a consultant, he held the IAAF marketing rights for much of Asia.

Coe has already visited Dentsu during his five months in office and the IAAF released a statement about its marketing partner saying: "The IAAF and its worldwide commercial partner Dentsu Inc. are in close and regular contact on all commercial matters.

"As part of such communication Dentsu's executive officer Kiyoshi Nakamura has expressed that 'we have full confidence in the new leadership of the IAAF and the reform process being led by current IAAF president Sebastian Coe and the IAAF world athletics series remains an important property within Dentsu's global sports business portfolio'."