Armitstead faced suspension for three failures relating to her whereabouts which led to her missing drugs tests.

But the Court of Arbitration for Sport (Cas) said procedures were not followed for one test, which was declared void.

The 27-year-old won Team GB's first medal, a silver, at London 2012.

"I have always been and will always be a clean athlete and have been vocal in my anti-doping stance throughout my career," she said.

Armitstead is considered one of the favourites to win gold in the women's road race at the Olympics in Rio on Sunday.

How the story unfolded

A statement on Armitstead's behalf said she was charged by UK Anti-Doping (Ukad) with three whereabouts failures on 11 July, leading to a suspension pending disciplinary action - and a possible two-year ban.

It said the first came at a World Cup event in Sweden on 20 August, 2015, the second was an administrative failure on 5 October and the third was a missed test on 9 June this year following "an emergency change of plans due to a serious illness within her family".

Armitstead did not dispute the second two faults, but successfully appealed to Cas over the first missed test, which happened at a team hotel in Sweden.

Armitstead undertook in-competition testing the following day, as leader of the UCI Women Road World Cup.

"Cas ruled that the Ukad doping control officer had not followed required procedures nor made reasonable attempts to locate Armitstead," the statement added.

"Cas also ruled that there was no negligence on Armitstead's part and that she had followed procedures according to the guidelines."

The news of Armitstead's missed tests was revealed by the Daily Mail, which said she was supported by a legal team funded by British Cycling.

A British Cycling spokesman said: "We are satisfied that the matter has now been resolved and look forward to Rio, where we have full confidence that the team will be a great success."

Armitstead added: "I understand how important it is to be vigilant in my role as a professional athlete and realise the potential implications this could have had.

"I would like to thank British Cycling and the team around me for all of their help and support. I am very much looking forward to putting this situation behind me and firmly focusing on Rio again after what has been an extremely difficult time for myself and my family."

A Ukad spokeswoman said: "We recognise that mistakes do happen and plans can change at short notice, which is why an athlete can accrue a combination of three missed tests or filing failures in 12 months under the World Anti-Doping Code.

"But athletes have a responsibility to ensure they support and follow the system, or they risk a possible two-year ban."

Christine Ohuruogu, the British 2008 Olympic 400m champion, was banned for a year following three missed tests in 2006.

(BBC)