Earlier this week, China revised down its forecast for economic growth this year to 7.3 percent from 7.4 percent.
The Chinese government set its target GDP growth rate for 2015 at 7 percent and, in July, it reported a 7-percent annualized growth rate. Nevertheless, Buiter added that based on the bank's models, China's economy grew at about 4 percent. "The official data is largely meaningless," he said.
"If China does worse, the U.S. and everybody else does worse. It is mitigated somewhat by weaker commodity prices," he added. "Chinese trade as a share for total world trade is larger than that of the U.S."
Buiter said that should China enter a recession, many emerging markets would probably follow.
"The advanced economies or developed markets (DMs) will not have enough resilience, either spontaneous or policy-driven, to prevent a global slowdown and recession, even though many large DMs will not experience recessions themselves but will merely grow more slowly," he added.