Actress Robin Wright says she and other cast members on the hit series House of Cards were "surprised" by allegations of sexual assault against co-star Kevin Spacey.

"We were all surprised of course, ultimately saddened," Wright said in an interview with NBC broadcast on Monday, describing her relationship with Spacey as "professional."

Spacey, a two-time Oscar winner, has been accused of attempting to rape a teenage boy and of a pattern of harassment towards younger, male colleagues — including on the set of House of Cards.

"We were co-workers, we never socialized outside of work," said the actress. "Ours was a respectful, professional relationship, he was so great with me, he was never disrespectful to me."

All the sexual misconduct accusations levelled so far against Spacey, who turns 59 later this month, have come from men.

Australian actor Guy Pearce, who starred alongside Spacey in the 1997 thriller LA Confidential, described him as a "handsy guy" who made him feel uncomfortable. "Thankfully I was 29, and not 14," he said.

Spacey has not been officially charged by police with any crime, although investigations into his behavior have been launched from London, where Spacey directed the Old Vic theater from 2004-2015 to Los Angeles and Nantucket, a coastal resort near Boston.

His acting career ground to a halt as a slew of accusations emerged in the wake of the #MeToo movement, triggered by a number of prominent women accusing Hollywood mogul Harvey Weinstein of sexual abuse.

As well as being fired from the House of Cards set, Spacey was also dropped from the Ridley Scott movie All the Money in the World and replaced by veteran actor Christopher Plummer.