His comments Thursday came after the bank raised its key rate Thursday by a quarter percentage point to 1.25 percent from 1 percent — the bank's first increase in nearly three years.
Trichet says inflation risks "remain on the upside" and that the bank would "monitor very closely" future price developments.
The bank must find a compromise between raising interest rates to prevent inflation as Europe's economy recovers and supporting crisis-hit countries and their banks. Portugal has asked for a financial rescue loan so it can pay its debts. Greece and Ireland have already been bailed out.