In one auction the state debt management agency, the IGCP, raised €800 million with the 11-month issue with an average yield of 0.037%, compared to an average of 0.100% at the last such auction in February.

In the other it raised €300 million with the issue of three-month bills, with a negative yield of 0.004% against a positive average yield in February's auction of 0.008%.

The declared target amount for Wednesday's operations had been €1 billion. Demand was 2.57 times supply in the case of the three-month bills and 1.41 times supply in the case of the 11-month bills.

According to Filipe Silva, director of asset management at Banco Carregosa, the current low rates could prevail “for some time yet” given the European Central Bank's declared intention of continuing stimulating demand by buying sovereign debt in the secondary markets, which “continues greatly to benefit the price at which Portugal borrows money”.