Real Madrid and Barcelona have been dealt a financial blow following the news that a new Spanish law governing the sale of television rights to broadcast football has been approved.
The regulation is being implemented from 2016 in order to bring La Liga more in line with fellow top leagues around Europe.
Under previous laws, Madrid and Barca were often able to negotiate lucrative TV deals which would allow them to dominate spending in the transfer market.
However, the new ruling will regulate the rights to transmit games in the Spanish first and second divisions, as well as the Copa del Rey and Spanish Super Cup, to see the income spread more evenly.
"You just have to see that last year the club that came last in the Premier League earned more than [champions] Atletico Madrid," sport ministry spokesman Miguel Cardenal said, before adding that Spanish football must "adapt to modern times".
The Premier League sold television rights to its games for a three-year period from the 2016-17 season for a record £5.136bn earlier this year.