And Europe's economy certainly needs all the help it can get. Gross domestic product (GDP) for the euro zone came in at just 0.2 percent in the first quarter, and there are ongoing concerns about the region's low inflation.
However, in spite of the record-low interest rate, lending to small and medium sized businesses – the backbone of the euro zone economy – has remained stubbornly low and continued to fall in April.
Another option open to the ECB is a cut in the deposit rate it pays banks to store money with it, which already stands at zero. As such, a negative rate would see banks charged for parking their cash at the ECB, giving them an incentive to move their money into other assets, such as loans to households and businesses.
A cut to either or both rates could also help weaken the euro, which has gained 4 percent against the dollar over the past year. A stronger single currency makes euro zone exports more expensive, thereby hindering the region's efforts to grow.
There are concerns that cuts to both interest rates have already been priced in to the market, which would significantly reduce their impact.
One issue with a cut to the refinance rate is that it doesn't leave much room for maneuver. If it is cut to yet another record low, the ECB would not have much scope to cut further before it turns negative.
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If the ECB crossed the threshold into negative deposit rates, it would be the first major central bank to do so – meaning it had moved into uncharted territory.
There are worries that such a move could hit the banking sector. If banks pass the negative rates onto customers, households and businesses could opt to hold onto their cash rather than deposit it in a bank. And if banks don't pass on rates below zero, their profitability could be hit as a result.
And even if the banks did offer more loans, companies may still be reluctant to take on more debt given the widespread uncertainty about the strength of the economy.
What the experts think
A large number of economists are expecting a cut to both the refinance rate – by between 10-15 basis points - and the deposit rate - by 10 basis points – to be announced by the ECB this Thursday.