But the bank did not commit to step up the pace of bond-buying, disappointing analysts who had been expecting further purchases to help calm markets.
ECB president Jean-Claude Trichet made no firm pledge to ramp up buying of government bonds to support the likes of Portugal and Spain.
The lack of a commitment came despite growing speculation that the ECB could rush through anti-crisis measures, including government bond buying on a much larger scale.
Klaus Baader, an analyst at Societe Generale, said: "It's a huge disappointment. There's no quantum leap, that's for sure. There's not even a little hop."
But shares in London shrugged off the ?news, closing up 2.2 per cent or 125.06 points at 5,767.56 in a second day of three-digit gains.
The ECB began purchasing bonds through its securities market programme (SMP) in May and has so far spent €67 billion (56bn), most of it during the first three weeks of the SMP.
As Trichet spoke, the premium that investors demand to buy Portuguese and Irish debt over German benchmarks fell, with traders saying the ECB was buying the bonds at a rate modestly higher than of late.
Speculation was rife in the run-up to the meeting that the ECB could rush through fresh anti-crisis measures with some analysts talking of trillions being spent to support peripheral eurozone debt.
Instead, Trichet urged eurozone governments to act, saying their actions would be of "decisive importance".