Del Nido, one of the most outspoken critics of the current system under which Real and Barca collect about 50 percent of the annual pot of around 600 million euros, compared his campaign on Tuesday to the French revolution.
He said as many as 15 of the 17 other clubs in the top flight had confirmed they would attend Thursday's gathering at Sevilla's Sanchez Pizjaun stadium, which would be a chance for discussion rather than a forum for taking concrete decisions.
"This is an uprising by the rank and file," Del Nido, a lawyer by profession, told reporters.
"We can compare it with the French revolution... and in the end look what happened to the king who was in charge in France.
"There is no going back here, as directors we cannot allow a situation where, because two clubs are very powerful, they bring about the demise of the Spanish league."
The difference in class and spending power between Barca and Real, the world's richest clubs by revenue, and their domestic rivals was underlined by their emphatic wins in their opening league games of the season.
Spanish and European champions Barca crushed Villarreal, who are competing in this season's Champions League, 5-0 at the Nou Camp, while Real demolished Real Zaragoza 6-0.
The results prompted the president of Villarreal to accuse the big two of killing Spanish football, while Del Nido said La Liga was "a load of rubbish" as only two teams had a realistic chance of winning the title.
BIGGER SHARE
Spain has yet to adopt the system of collective bargaining and income sharing used in other competitions such as the English Premier League and Real and Barca get a far bigger share of TV money than rivals in other major European leagues.
The pair brokered an agreement late last year with 11 other top-flight sides that would introduce limited revenue sharing from 2015.
However, analysts have said the deal, which Sevilla, Villarreal, Athletic Bilbao and several others refused to sign up to, was likely to cement the big two's advantage while helping the other clubs only marginally.
"We are going to open a debate to try to solve a problem on which we are all agreed," Del Nido said. "The television broadcasters will do what the league says.
"If the clubs decide to market their audiovisual rights collectively, it will be done by the body that we decide and that decision will be a majority one."
Real declined to comment on Del Nido's initiative, while Barca did not immediately respond to a request for comment.
Miguel Guillen, president of Sevilla's city rivals Real Betis, was quoted as saying in local media on Tuesday that when clubs came to negotiate their new contracts with broadcasters they would try to end Real and Barca's hegemony over TV cash.
Most of the current deals expire around 2014.
"Talks on 2014 will be held at the appropriate time but one thing is for sure,"
