According to Portuguese TV channel SIC, the country's anti-doping authority have decided on the punishment because of the coach's alleged behaviour during a testing session at a training camp in the run-up to the World Cup.

The former Real Madrid coach is already serving a one-month ban handed to him by the Portuguese Football Federation (FPF) because of the same incident, putting him out of action for the upcoming Euro 2012 qualifiers against Cyprus and Norway.

He was also fined 1,000 euros for misconduct when he was found to have acted aggressively towards the testers, but the disciplinary committee (CD) stopped short of finding he had interfered with proceedings.

Today both Queiroz and the federation said they had not been made aware of the decision of the anti-doping authority (ADoP).

In a statement released through his solicitors, Queiroz said: "According to some reports, the ADoP has found proof - unlike the CD of FPF - of breach and disturbance of anti-doping activity and has determined a six-month sentence.

"Neither I nor my solicitors have received any notification of this, making - if it is confirmed - the media the first to be informed of the decisions, ahead of the accused.

"As for me, what matters is not the decision, but the lack of any wrongdoing (as was recognised by the FPF). So I confirm that I will appeal this decision to the right institutions, namely to the Court of Arbitration for Sport (CAS).

"I will request, based on the statutory rules of CAS, that the decision be suspended until the appeal is heard."

The FPF refused to comment on the reports, as they awaited official notification.

A statement on the federation's website read: "Further to reports regarding the anti-doping authority's decision to punish national coach Carlos Queiroz, the Portuguese Football Federation has not been notified of the decision, so it will not make any comment until after further investigations."