Though U.S. stocks shaved morning declines, the stock market still appears weak, veteran trader Art Cashin told CNBC on Monday.
"I think people are trying to nail down profits. The markets are a little vulnerable here," Cashin, director of floor operations at the NYSE for UBS, said on "Squawk on the Street." "We have both the geopolitical things ... and people worried about going into the, if you would, September, October syndrome."
Indeed, geopolitical tensions continue to mount. Pro-democracy protests in Hong Kong added to ongoing unrest in Iraq and other troubles in the Middle East, he noted. Additionally, some polls show Brazilians are split between two candidates in the South American country's presidential election.
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In late-morning trade, the Nasdaq reversed falls to turn positive briefly before trading in the red again. The Dow and also regained ground after dropping about 1 percent at the open.
To Cashin, the markets only clawed back after the S&P on Monday retreated to 1,964, a key technical level that served as support.
Looking forward, Cashin is taking a "wait and see" approach, noting the markets will likely move on upcoming Jewish and Muslim holidays as well as Friday's jobs report and a European Central Bank meeting.
—CNBC's Evelyn Cheng contributed to this report.