Banco Central de la República Argentina on Aug. 12 raised interest rates in daily auctions to 74%, La Nación reported. The action came in a bid to contain a run on the peso following a surprise opposition triumph in the presidential primary elections on Sunday.

The benchmark interest rate is based on the central bank instrument Leliq. Auctions of 13.99 billion pesos worth of the note on Monday left the rate at over 1,000 basis points more than at the end of the last week, according to the publication, which cited unnamed central bank sources. The rate stood at 63.71% on Aug. 9, according to the central bank's website.

The regulator was preparing a new Leliq auction for Monday afternoon worth about $50 million, La Nación reported. The transaction could alter the benchmark rate further, as the central bank tries to weather the storm following a resounding defeat of Mauricio Macri's ruling party at the polls.

Argentine bank and local assets plummeted on Monday, as Peronist opposition candidate Alberto Fernández took an unexpected 15.5-point lead over incumbent Macri in the presidential primaries Aug. 11, making him a clear favorite for the October elections.

The currency lost about a third of its value against the U.S. dollar as of midday Aug. 12, following the news of the primaries. The country's banking stocks fell as much as 55% in dollar terms during morning trading. The country risk index is also expected to shoot up, reflecting a fall of 30% in short term bonds.

The central bank adopted the current monetary scheme in October 2018, working along with the International Monetary Fund program, after severe market volatility had seen the Argentine peso fall dramatically and yearly inflation spiral over 50%.

The regulator has not made a statement on its plans at the time of this writing.

As of Aug. 9, US$1 was equivalent to 45.45 Argentine pesos.