A recent bounce in oil from multiyear lows indicate prices have "probably bottomed," but the spike on concerns about Saudi Arabia's military operation in Yemen could portend a rough patch for the stock market, closely followed investor Dennis Gartman said Thursday.
"If we're seeing this sort of activity in the crude market, this sort of rapid rise higher predicated upon the problems in the Mideast ... [it] does make it more difficult to be bullish on stocks," the founder and publisher of The Gartman Letter said on CNBC. "It's probably time to be less bullish [on stocks]. It's probably time to be less involved. It's probably time to reduce one's exposure a bit."
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After three-straight down days, the stock market opened sharply lower Thursday, with the and Nasdaq composite joining the Dow Jones industrial average in negative territory for the year.
"We have some problems here. We may well have an interim top of some sort," Gartman said in a "Squawk Box" interview. "We've seen far too little leadership on the upside … [and] far too much parabolic toppy-type action in the biochemicals, in the pharmas. That sort of activity bothers me greatly." He also cited the Federal Reserve's likely interest rate hike later this year as a factor.
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Still, he thinks the six-year bull market in stocks remains intact. "I don't think the bull market in stock prices has seen its best levels yet."
As for oil, the recent rise in battered prices, accelerated Thursday by Saudi-led airstrikes in Yemen, indicate that a bottom has likely been seen, Gartman said, with U.S. crude bouncing off $42.03 a barrel on March 18.
But he's not ready to call a dollar top against the euro. "I would hesitate saying that the dollar has seen its best levels, that the euro has seen its worst."
"If crude oil has seen its lows, the odds are better that the dollar has seen its highs," he said. "But I'm not quite willing to make that statement yet."