While stories about the rise of filmmaking talent from Mexico and the unofficial brotherhood among the country's most esteemed directors and writers claimed a fair share of ink in the months leading up to this year's Academy Awards, it turns out there is more unrest than first thought south of the border. 

The nearly decade-long partnership between director Alejandro González Iñárritu and writer Guillermo Arriaga is on the skids after a letter published Monday in the Mexican magazine Chilango took Arriaga to task for supposedly hogging the Babel spotlight. 

"It's a shame that in your unjustified obsession to claim sole responsibility for the film, you seem not to recognize that movies are an art of deep collaboration," read the letter, which was signed by, among others, González Iñárritu, costars Gael García Bernal and Adriana Barraza, director of photography Rodrigo Prieto and Argentine composer Gustavo Santaolalla, whose original score won the film its sole Oscar Sunday.  

(This was Santaolalla's second win in a row, having been honored last year, as well, for Brokeback Mountain.) 

González Iñárritu and Arriaga were up for Best Director and Best Original Screenplay, respectively, before losing out to The Departed's Martin Scorsese and Little Miss Sunshine scribe Michael Arndt. 

"You weren't—and you never let yourself feel like—part of the team, and your comments are [a] lamented and belittling end to this marvelous and collective process that we have all experienced and are now celebrating," the letter continued, per an excerpt posted on the blog Vivir Latino.  

González Iñárritu goes on to wish Arriaga "luck in your future movies." 

Arriaga, in turn, lashed out at González Iñárritu in a radio interview, saying that the director stole his thunder by listing himself in the credits as Babel's main creator. 

"I tried to defend the collective nature of the film," Arriaga said. "It belongs to everyone." 

Babel, which was named Best Motion Picture drama at the Golden Globes last month, was the third high-profile collaboration for González Iñárritu and Arriaga, who are also responsible for 2000's Amores Perros (also featuring García Bernal and Barraza) and 2003's 21 Grams, both flashback-happy ensemble dramas that, like Babel, deal with freak occurrences causing a handful of seemingly disparate lives to intersect in surprising ways. 

In both Amores Perros and 21 Grams, it's a fatal car accident that sets subsequent events in motion. 

According to the Mexican newspaper El Pais, Arriaga has said that González Iñárritu took an "extreme position" by referring to their three films together as "my trilogy," and that there are other people who worked on Babel who would support Arriaga's version of events. 

In an interview with the Hollywood Reporter earlier this month, in which Babel is described as being based on an idea by both the writer and González Iñárritu, Arriaga went into more detail as to how and why the duo split the credit.  

"It is credited to him because I had this story first placed only in two countries," Arriaga said. "He asked to have it in four and that's why he has the 'idea by' credit." [The story originally took place only in Mexico and the United States. The finished film extends to Morocco and Japan.]  

But, Arriaga told the trade, the final product follows his finished screenplay almost to the letter, except for a brief scene added during filming in which the nanny played by Barraza kisses an old man during the wedding sequence.

"I have been fortunate that the movies I have been involved with have been [shot] pretty close to the screenplays."   

Meanwhile, Arriaga, who also penned Tommy  Lee Jones' directorial debut, 2005's The Three Burials of Melquiades Estrada, has already distanced himself from González Iñárritu, saying last year that their working relationship had ended due to creative and personal differences.