Buenos Aires, Argentina | In tango, a male dancer leads his female partner through a series of sensual and synchronized movements. The man always leads -- but Argentina's "queer tango" turns this convention upside-down.

Subverting the lead male role is nothing short of revolutionary in the rigid world of tango dancing, and faces resistance from traditionalists.

"Tango is a reflection of society, a social code where men have the power," said Yuko Artak, an instructor at a queer tango lesson in Buenos Aires.

She then gives a demonstration.

"One, two, three," Yuko says, guiding her partner, Liliana Chenlo, as music plays in the background.

The women halt in mid dance, switch position, and Chenlo leads Artak.

Tango originated in the late 19th century in the River Plate region, between Argentina and Uruguay. Legend has it that it began as men dancing with men in brothels.

As the dance grew in popularity and became accepted among the middle class, women were allowed to join, though always led by the man.

"Queer tango seeks to break up that code... to shatter the exclusive male-female pairing of the dance," said Artak.

Alexis and Ignacio, who declined to give their last names, are excited about their queer tango lesson.

"It's good to be able to get out of the forced masculinity, and see the tango as movement," Ignacio said.

- Trailblazing -Tango purists had already raised their eyebrows at Astor Piazzolla, the late creator of "Libertango," who revolutionized the dance with a contemporary vibe that incorporated jazz-style music.

Queer tango is facing just as much, if not more, resistance.

Two women were kicked out of a tango dance at a town square in Montevideo in March when they danced as partners.

"People's minds are a bit closed on this topic," Chenlo said, with a knowing smile.

This year, she and Artak took the daring step of signing up to compete in the World Tango Championship in Buenos Aires.

Some 500 couples from 45 countries entered the event, including three gay couples -- one from Russia, and another from Argentina besides Artak and Chenlo.

For the competition, Chenlo performed the lead role throughout, a concession "to not confuse the public and the jury", she explained.

Nevertheless in their attire and presentation, "we emphasized that we were two women who dance tango together", Chenlo said.

Some dancers congratulated the couple as they awaited their turn.

A member of the audience however was aghast.

"Those are two women!" said Julian Sotelo, a 74-year-old retiree dressed in a striped suit, the kind often used by tango dancers. 

Sotelo squirmed in his seat when he saw the pair climb onto the stage.

"That's not tango," he mumbled with a half-smile, even before the dance began.

Both Artak and Chenlo believe that their participation in the World Tango Championship will help people accept queer dancers.

"When people realize that tango is just hugging and dancing, then all the issues of gender will be erased," Chenlo said.