The convicted mafia boss Domenico Rancadore has been remanded in custody after appearing in court over his connections to the crime syndicate following his rearrest.

Officers from the Metropolitan police's extradition unit detained the 65-year-old in Uxbridge, west London, on Friday after they received a new European arrest warrant request from Italy.

Rancadore appeared at Westminster magistrates court in central London on Saturday, where he was described as "one of the heads of one of the most powerful mafia associations in Italy" by Adam Harbinson, representing the Italian authorities.

Harbinson told the court that the latest arrest warrant is identical to the previous one – successfully fought by Rancadore – save for assurances about the prison conditions he would be faced with in Italy.

Concern that the country's jails would breach his human rights is what won him the previous battle against extradition. Rancadore, known as the Professor, was arrested last August after evading Italian authorities for 20 years.

They accuse him of fleeing Italy where he faced trial over his alleged Cosa Nostra "man of honour" connections.

The arrest warrant alleges that Rancadore has an "outstanding sentence of seven years' imprisonment to serve for participation in mafia association" between 1987 and 1995 in Palermo.

Wearing a beige sweater, blue shirt and black trousers, Rancadore waved to his wife, Anne, in the public gallery.

He was remanded in custody to appear at the same court for a bail hearing next week.

Last month Howard Riddle, a senior district judge, reversed his original decision to extradite Rancadore, who has a serious heart condition, after concerns that prison conditions would breach his human rights.

He was later told at another hearing that he would not face an appeal against the judge's ruling.

The high court heard the Crown Prosecution Service had lodged an appeal against the decision to refuse Rancadore's extradition but it was not served to his lawyers within the seven-day time limit and he was released on unconditional bail.

Rancadore and his wife moved with their two children to Uxbridge in 1994 and lived under the name of Skinner, the maiden name of Anne Rancadore's British mother.

At a previous hearing, Rancadore said he came to the UK to give his children "a good life", and to bring his time in Italy to an end.

He said the maxi-trial in which he was a defendant in the mid-1980s – involving 460 defendants, one of whom was his father – was a "terrible experience".

Asked about changing his name to Marc Skinner, he said it was to end ties with Italy, adding: "This was the only way."

Rancadore said he did not even contact his mother or father back home, saying: "I wanted to end everything with Sicily."