The United States Composite PMI Output Index landed at 54.4 in September, slightly down from 54.6 registered in August, S&P Global reported on Monday.

The report revealed a slight slowdown in manufacturing activity in September, with the Flash US Manufacturing PMI dropping to 47.0 from 47.9 in August. While the service sector continued to fall slowly, manufacturing output rose to its highest level in two months, reflecting uneven growth across industries.

"The early survey indicators for September point to an economy that continues to grow at a solid pace, albeit with a weakened manufacturing sector and intensifying political uncertainty acting as substantial headwinds. A reacceleration of inflation is meanwhile also signaled, suggesting the Fed cannot totally shift its focus away from its inflation target as it seeks to sustain the economic upturn," Chief Business Economist at S&P Global Market Intelligence, Chris Williamson, said.