Former All Black Ali Williams in cocaine plea deal - reports

As former All Black Ali Williams reportedly reached a deal with prosecutors after being charged with buying cocaine, details of his weekend in the cells have emerged.

Williams, 35, was arrested on Saturday (NZ time) in Paris, along with former Wallabies player James O'Connor outside the L'Arc nightclub.

French media report Williams has made a plea deal with authorities over the charge and will appear before a judge and prosecutor in a closed court hearing later this week.

Meanwhile, more details of that night have emerged - including the 40 hours the international rugby players spent in police cells alongside gang-affiliated criminals.

Williams is thought to have got into a car with the two alleged drug dealers, buying 2.4 grams of cocaine and handing over €200 in cash, The Daily Telegraph reports.

O'Connor was acting as the lookout.

As they went to walk back to the nightclub, undercover police pounced - at which point Williams allegedly threw three packets of cocaine on the ground.

They were arrested and taken to three separate police stations; in the first they were put into "sobering cells" alongside others who were on drugs or had drunk too much alcohol.

The third station held more hardened criminals, some of whom were linked to violent gangs, The Daily Telegraph reports.

The pair were kept separated.

Police kept an eye on the pair before they received drug test results.

O'Connor allegedly tested positive result for cocaine, but because he didn't touch the drugs during the arrest was only given a fine for "intent" to consume the drug. Williams tested negative.

O'Connor comes off-contract with his Toulon club in July and had been re-negotiating his contract, though the drug incident has put things on hold.

Williams, however, has been suspended from his Racing92 club. There are also reports the French Rugby Federation is looking to ban Williams from playing rugby in the country.