The European Central Bank (ECB) is highly likely to keep interest rates on hold today.
Nonetheless, President Jean-Claude Trichet needs to signal a rise in June without driving up rate expectations for later this year.
Analysts expect the ECB's Governing Council to leave the benchmark rate at 2.5 per cent at its monthly policy meeting and wait for solid first quarter data to show how fast the economy is strengthening.
But Mr Trichet, who last month all but ruled out a move in May, will probably make clear the ECB is preparing an increase next month to tackle its concerns about inflation from rising oil prices and money supply, and falling spare capacity in the economy.
"I don't think they'll change interest rates. They'd look pretty silly after what they said last time," ABN Amro economist Dario Perkins said. "But given the way they've acted over the last six months they should sound quite hawkish. They want to cement the view that they should raise rates in June."
Mr Trichet stunned markets last month when he said he did not support market expectations of a rate rise as soon as May but that he was more sympathetic to a June increase.
In the past month, other ECB policymakers have said more than one rate rise is needed this year, consistent with market expectations of rates reaching at least 3 per cent by year-end.
However, Mr Trichet will have to pick his words carefully, as too hawkish a tone might lead money markets to infer a faster pace of rate rises for the rest of 2006 - whereas some ECB watchers say the central bank usually intends to give guidance only a month ahead.
Most analysts expect only a quarter percentage point rise in June, mirroring increases in December and March. But some have raised the outside chance of a half percentage point rise, which would be the ECB's most aggressive move in six years.
It is unlikely that Mr Trichet will resist commenting on inflation, which rose to 2.4 per cent in April and is above the ECB's target of price growth below, but close to 2 per cent.
Money supply and credit growth, which the ECB views as a medium term inflation risk, have also risen fast, and private lending reached a historic peak.
This could prompt Mr Trichet to say the ECB needs to be "vigilant" towards price rises, a past signal that a rate rise was due soon.