BRASILIA, Jan 18 (Reuters) - Creditors of Brazilian engineering firm OAS SA could demand early repayment of around 1.5 billion reais ($572 million) in debt after it failed to pay interest on bonds earlier this month, newspaper O Estado de S.Paulo reported on Sunday citing an OAS document.
The company's cash and marketable securities were estimated at 1 billion reais as of Dec. 31, 2014, according to Fitch Ratings. The agency downgraded OAS debt by five notches to 'C' after it missed a coupon payment on its bonds maturing 2021.
OAS estimated the total debt eligible for early repayment claims in a letter to one of its bondholders, Credito Corporativo Brasil, to explain its efforts to restructure obligations with its creditors, Estado said.
OAS spokespeople did not respond to a request for comment.
$1 = 2.62 Brazilian reais Reporting by Silvio Cascione