Two siblings from the famed circus act the Flying Wallendas have completed a death-defying stunt, crossing New York’s Times Square on a high wire strung between two skyscrapers 25 storeys above the pavement.

Nik Wallenda is a seventh-generation acrobat, but this time, he said he was nervous.

His sister, Lijana Wallenda, joined him on Sunday night for the first time since her near-fatal accident in 2017, when she broke nearly every bone in her face.

The siblings walked from opposite ends of the 1,300-foot wire suspended between the towers, crossing each other in the middle, where Lijana sat on the wire and let her brother step over her.

Both then continued to the opposite side.

Their latest daredevil stunt was streamed live on US network ABC and watched by thousands of spectators from below.

Nik Wallenda was joined by his sister Lijana for the daring stunt
Nik Wallenda was joined by his sister Lijana for the daring stunt (AP Photo/Jason Szenes)

The two were wearing tethered safety harnesses required by the city in case they fell.

The Wallenda family has been a star tightrope-walking troupe for generations, tracing their roots to 1780 in Austria-Hungary, when their ancestors travelled as a band of acrobats, aerialists, jugglers, animal trainers, and trapeze artists.

They never use nets in live shows or in rehearsals.

In 1978, 73-year-old Karl Wallenda fell to his death from a high wire strung between two buildings in Puerto Rico.

The high wire was suspended 25 storeys above the pavement
The high wire was suspended 25 storeys above the pavement (AP Photo/Jason Szenes)

In 1962, Karl Wallenda’s nephew and son-in-law died, and his son was paralysed, after a seven-person pyramid collapsed during a performance.

Lijana’s fall happened during an attempt to break a Guinness world record with an eight-person pyramid.

Nik’s high-wire walks above Niagara Falls, the Chicago skyline, and the Little Colorado River Gorge near Grand Canyon National Park were broadcast on national television.