Online betting sites have gone offline in Brazil following the entry into force of a ban on online gambling in the country at midnight on October 6, while some of the country’s biggest football clubs have already begun ending their sponsorship agreements with betting companies.

The crackdown on online gambling follows a provisional measure signed by President Luiz Inácio Lula da Silva, which set a 11:59 p.m. deadline on Monday for betting companies to take their websites and related advertising materials offline.

Until the last minute, there had been expectations that the Supreme Federal Court could issue an injunction suspending the effects of the measure, but no such decision was made.

This means betting companies will also have to step away from their strong ties with Brazilian football clubs, including major brands such as Betano and Sportingbet.

The end of betting advertising is expected to have an impact of more than R$1 billion on clubs in Brazil’s top-flight Serie A.

Atlético Mineiro became the first club to end a deal with a betting company that was its main shirt sponsor, announcing carmaker BYD as the replacement for Bet da Sorte on the front of its shirt.

The provisional measure will still have to be approved by Congress to become permanent, but it took immediate effect.

The decision to ban online gambling, including sports betting and the popular “Tigrinho” game, was taken by Lula da Silva in an effort to tackle an addiction that has contributed to a significant increase in household debt.