Spanish public deficit was 9.4 percent in 2011, according to data released on Monday by the European Union's statistical office Eurostat.

This implies a 0.9-percent increase over April when Eurostat predicted a public deficit of 8.5 percent. The increase is said to be because of unpaid invoices and capital injections to financial entities.

Eurostat said unpaid invoices by the all levels of public administration caused a 0.4 percent increase in the deficit, while capital injections to struggling financial entities such as CatalunyaCaixa, NovaGalicia Banco and Unnim explained the remaining 0.5 percent increase.

Eurostat also revised up its estimate for Spain's 2010 public deficit from 9.3 percent to 9.7 percent. Again, unpaid invoices by the central government and regional administrations explained the increase.

The data confirms Spain reduced its public deficit by 0.3 percent between 2010 and 2011.

Last September, the Spanish government said public deficit in 2011 was 9.44 percent, taking into account capital injections to the banking system. Without this factor, the deficit would have been 8.96 percent.

Eurostat forecast the deficit to reach 7.4 percent at the end of 2012 as opposed to the 6.3 percent required by Brussels and predicted by the Spanish government.

However, capital injections to the banking sector are not taken into account in the public deficit figure required by the EU.