Trichet dismissed the idea that a rate rise in April could be bigger than 25 basis points, saying that such a scenario was "not the appropriate interpretation".
"The position of the Governing Council is that an increase in interest rates at the next meeting is possible," he told a news conference after the ECB left rates at a record low one per cent.
Asked whether a potential rate rise in April would signal the start of a round of hikes, he added: "It is certainly not the sense of the start of a series of rate hike increases."
The euro soared as Trichet spoke, piercing resistance around $1.3958, its 200-week moving average, to hit as high as $1.3976, its strongest since November 8 and putting it on track to test the psychologically important $1.40 level.
“Trichet set alarm bells ringing when he opened the press conference leaving out his familiar comment that rates ‘remain appropriate’ and going on to say that ‘strong vigilance’ was warranted to contain risks to price stability,” said Investec analyst Philip Shaw.
“‘Strong vigilance’ was the phrase the bank prolifically used during the 2005-2007 rate hike cycle, typically one month before it raised rates. The statement is clearly intended to signal to markets that a rate hike is close.”
Trichet said an April rate rise was not certain but sounded notably hawkish.
"When we have a shock – and we have a shock – our responsibility is to prevent a second round of effects (from high oil prices)," he said.