Art Cashin, the head of New York Stock Exchange floor operations for UBS, said he doubts the Federal Reserve will be able to raise interest rates again this year because of underlying weakness in the U.S. economy.

"The Fed is going to have to wake up. I don't think the economy is as good as it looks," Cashin said on CNBC. "The inflation numbers were not good. Retail sales were not good."

Cashin spoke one day after Fed policymakers approved a 0.25 percentage point hike, the second increase of 2017 and the highest in nine years. The central bank forecast another rate increase later this year, alongside efforts to reduce its trillion-dollar holdings of U.S. government debt.

The economy grew at a 1.2 percent annualized rate in the first quarter, slowing from the 2.1 percent pace in the October-December period. The Atlanta Fed forecast that economic growth will accelerate to 3.0 percent annualized rate in the second quarter.

Data on retail sales, manufacturing, wage growth and inflation don’t support the idea of a vigorous economy, though. The Fed said inflation likely will be less than its 2 percent target this year

"It's not that the economy is on life support but it's certainly not robust," Cashin said. "It's not ready to do a marathon yet."

Traders tracked by the Chicago Mercantile Exchange don't expect the Fed to raise rates in September or December. The CME FedWatch Tool indicates a market estimate of a rate hike in March.

Another worry is that President Donald Trump’s pro-business economic agenda will be derailed by multiple probes into connections between Russia and his presidential campaign. The Washington Post reported that special counsel Robert Mueller is investigating Trump for possible obstruction of justice, a criminal charge.

"Washington is going to be occupied with the investigation, and we won't get to see tax reform, we won't get to see any of the things that they were hoping for," Cashin said.

Weakening oil prices that may indicate commercial activity isn’t strong enough to reduce a glut in energy products also hurts.

"If oil sells off again and breaks $44, it will have a very negative influence on the market," Cashin said.

West Texas Intermediate crude traded at $44.41 a barrel on Thursday afternoon, below the 200-day moving average of $49.74.

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