Supporters of Argentine Vice President Cristina Kirchner -- on trial for alleged corruption -- gathered across the country on Saturday, with police using tear gas and water cannon in the capital Buenos Aires.

Kirchner, 69, is accused of fraudulently awarding public works contracts in her stronghold in Patagonia, and prosecutors have asked that she face 12 years in jail and a lifetime ban from politics.

Thousands responded to a social media campaign and gathered peacefully in town squares across Argentina, though in Buenos Aires some supporters breached police barricades to reach Kirchner's home.

"There has been too much blood in Argentina for them to continue threatening those who think differently with gunfire, bullets, tear gas and pepper spray," Kirchner told supporters.

The ex-president, who ruled from 2007 to 2015, called on her opponents "to stop competing among themselves" about who hates Peronists more, referencing the political movement she subscribes to, based on the ideas of former ruler Juan Peron.

"It is incredible the degree of cynicism and perversion of not assuming and taking charge of what they want: to exterminate Peronism," she said.

Kirchner is the Senate president and enjoys parliamentary immunity.

Even if convicted -- the verdict is expected at the end of the year -- she would not go to prison unless her sentence was ratified by the country's Supreme Court, or she loses her Senate seat at the next elections at the end of 2023.