Investors should be wary of a steepening yield curve in the U.S. Treasury market, according to Pacific Investment Management Co.’s Mohamed El-Erian.

While yields on government securities due in eight years and less are anchored by Federal Reserve monetary policy, there is “a lot more risk” in longer-maturity debt, El-Erian, the chief executive officer of the world’s largest manager of bond funds, said in a “Bloomberg Surveillance” radio interview with Tom Keene and Ken Prewitt.

The difference in yields between two- and 10-year Treasurys widened to 1.42 percentage points, or 142 basis points, the most since May.

Investors often demand a bigger yield premium on longer-maturity debt to guard against the risk that inflation will erode the value of fixed payments from the securities over time.