Halliburton has joined rival Schlumberger in curbing activity in Venezuela due to lack of payment during the oil industry’s worst financial crisis. “During the first quarter of 2016, we made the decision to begin curtailing activity in Venezuela,” Halliburton, the world’s second-largest oil services provider, said, according to Bloomberg, in a filing with the US Securities and Exchange Commission.

“We have experienced delays in collecting payment on our receivables from our primary customer in Venezuela. These receivables are not disputed, and we have not historically had material write-offs relating to this customer,” the company said.

Halliburton’s receivables in Venezuela rose 7.4% in the first quarter to $756m compared to the end of 2015, representing more than 10% of its total receivables, Seeking Alpha wrote. It’s the only country or customer that represents more than 10% of receivables, it said. Halliburton, however, did not name the customer in the filing.