Renewed trade war fears triggered a bond market recession indicator on Thursday.

The yield on the 10-year Treasury note fell below that of the 3-month bill Thursday morning, inverting part of the yield curve. The yield curve is the plot of interest rates of bonds having equal credit quality but differing maturity dates. An inversion has been a reliable recession indicator in the past, though there is a debate over which segment of the curve is most important.

The Federal Reserve — as well as President Donald Trump's chief economic advisor Larry Kudlow — consider an inversion of the 3-month and 10-year curve as a key barometer.

By Thursday afternoon, the yield curve between the 3-month bill and 10-year note had steepened and was no longer inverted. At 4:22 p.m. ET, the yield on the benchmark 10-year Treasury note, which moves inversely to price, was lower at around 2.451%, while the yield on the 3-month Treasury bill yield hovered at 2.432%.

"I think that we're going into a recession. Look, I'm not going to sit here and pinpoint the day, the week or the month it's going to happen, but it's out there," said David Rosenberg, chief economist at Gluskin Sheff. "I think people tend to forget that the cause of the recession are the lags between the monetary policy tightening cycle and the eventual hit on GDP growth."

"So of course we're talking about trade right now, but my premise all along is that there is no 'get out of jail free' card after you've had a monetary policy tightening cycle like we had," he added.

Traders are closely following trade relations between the U.S. and China, as tensions continue to grow. On Wednesday, Trump said that China "broke the deal."