The euro's recent gains against the dollar are set to continue for the meantime, but investors should be cautious as the greenback's declines could be about to change, Roelof van den Akker, chartist at ING Wholesale Banking, told CNBC Tuesday.
"It's still within an uptrend from its June lows at $1.18. It's showing a clearly rising trend, but there are some warning signals here," van den Akker said.
"Last week prices broke above $1.40 and a half, but failed to continue this sharp up move so we see the first signs of a somewhat toppish outlook," he said.
If the euro closes below $1.3670, then investors should be prepared for a decline to around $1.33, he added.
If that level isn't broken, investors can assume that the overall trend is still intact and the euro is set for another leg higher against the greenback, he said.
Meanwhile, the price of oil, which has been boosted by the dollar weakness, could be set for a rally toward around $93 a barrel, van den Akker said while taking a technical look at the West Texas intermediate (WTI) chart.
If WTI breaks above $83.40 a barrel, then the $93 figure could not be far off, he said.