Spanish Public Works Ministry officials have said publicly that the privatisation of AENA, Spain's airports authority, should take place before the end of the year. The sale of AENA has been a popular topic for years, last shelved in 2011 because of poor market conditions and because a change in the government.

AENA is the world's largest airport authority. It is entirely owned by the state and runs 46 airports in Spain and 23 airports abroad. Spain has popular beach destinations in Europe and is a hub for Latin America. It welcomed nearly 58 million visitors in 2012.

AENA's has €12 billion of debt. Its value could be between 12 billion and 15 billion euros or 8 to 10 times this year's core earnings (EBITDA). The government would aim to raise around 6 billion euros, according to local sources.

The government has named Lazard and N+1 as its advisers. Government officials however for the moment have only talked of the sale of a minority stake, although a decision to sell more would boost the value of the offering.

The operator recently raised airport tariffs to bring rates into line with European peers.