Petrobras faces a multibillion-dollar tax bill over the oil giant’s chartering of vessels to foreign companies after an administrative panel rejected an appeal.

The Rio de Janeiro-based company said that a panel of the Superior Chamber of Tax Appeals issued an “unfavourable ruling” that could cost it BRL 18bn ($3.4bn).

Petrobras said the ruling involves import duties on charter deals for vessels from international markets in 2010, 2011 and 2013.