Brazilian oil firm Petrobras downgraded to junk status by Moody's

Brazilian oil firm Petrobras has now been downgraded to junk bond status by Moody's.

The ratings agency said in a Tuesday night note that a kickback scandal engulfing Brazil's biggest company is an "increasing concern."

The downgrade means it'll be even harder for Petrobras to obtain credit on international markets — and if it does it'll be more expensive.

It's the latest blow to hit Petrobras. In recent months it has been at the center of what prosecutors say is the biggest corruption scandal yet uncovered in Brazil.

Investigators say executives from construction and engineering firms paid bribes to win inflated contracts on projects worth tens of billions.

They also say some of the money was funneled back into the campaign coffers of the ruling Workers' Party and its allies.