Argentina ADRs slide after Milei's ruling party records heavy defeat in Buenos Aires

** U.S.-listed shares of Argentine companies decline premarket after President Javier Milei's ruling party saw a heavy election defeat in Buenos Aires province

** Provisional official tally on Sunday showed opposition Peronist party triumphed in legislative elections, President Milei's party in distant second place

** "While we assess that the provincial election stands to have a very limited effect on the policy mix of the Milei administration, it does represent a political setback for the government," Goldman Sachs analysts say in a note

** Financials including Grupo Supervielle SUPV.N, Banco Macro BMA.N, Banco BBVA Argentina BBAR.Nand Grupo Financiero Galicia GGAL.O slide between 6.7% and 14.5%

** State-run oil company YPF YPF.N slides 10.3% and gas transportation firm TGS TGS.N down 5.5%

** Global X MSCI Argentina ETF ARGT.P declines 8.6%

** Investors say early market indications priced 5 to 6 point falls in the country's international bonds as well