Shares of Sprint Nextel Corp. slipped Wednesday as Standard & Poor's warned it may cut the wireless provider's credit rating based on the its "weak" performance this year.
Sprint, the country's third-largest carrier, has been losing money and customers despite cutting its rates and introducing new phones.
"We remain concerned that the company may have difficulty in improving operating trends as industry conditions mature and competition intensifies," S&P analyst Allyn Arden said in a statement.
Arden said Sprint's debt level is likely to "drift" higher given the company's trajectory.
The agency put Sprint's non-investment, or "junk" grade, "BB" rating on "CreditWatch" with negative implications.
Shares of Sprint, which is based in Overland Park, Kan., fell 9 cents, or 2.8 percent, to $3.15 in midday trading.