The Spanish government has already pledged to spend €20bn (£16bn) on council housing and small to medium-sized businesses in 2008/9.
New measures to reform the transport sector – likely to include extending the new high-speed AVE train network – will be announced in October.
The Spanish government said it would "boost and dynamise" rail freight and "improve the conditions of competition and competitiveness" to deal with rising fuel costs that are aggravating the European economic crisis.
The announcement came as part of a package of 24 economic reforms put forward by Spanish president José Luis Rodríguez Zapatero last week.
However, as Spain has a budget deficit of some 10% of its Gross Domestic Product, it is likely to fund new infrastructure schemes indirectly, possibly through private finance, to ensure that this deficit does not increase, and is brought to within the European Union's deficit limit of 3%.