LOS ANGELES • Nicki Minaj has upped the ante in her feud with Cardi B, saying both rappers should submit to lie-detector tests to find out who is speaking the truth.

On Monday, on her Beats 1 Queen Radio show, Minaj said Cardi B had been attacked by Rah Ali, a friend of Minaj's, "nine or 10 times" at a New York Fashion Week party last month.

"Rah beat you so bad, I was mad at Rah. You went home and told people security hit you," she added.

"There is no way I can lie about this because there is surveillance footage from the building where the assault took place," she noted.

"Anyone who wants to put up the surveillance footage, I will give you US$100,000 (S$138,000)."

Cardi B, in response, wrote on Instagram: "You lie so much, you can't keep track of your lies. First you say you've got the footage, but then you say you wanna pay somebody US$100,000 if they give you the footage? Yo, make sense when you're talking."

Minaj, on her show, also denied a claim from Cardi B's sister that she had leaked the rapper's phone number to her fans, reported trade publication Variety.

But Cardi B was unconvinced, revealing in a follow-up post that her number had been leaked just an hour after the Fashion Week fracas.

Minaj shot back, tweeting: "I'll pay you to take a lie-detector test about every claim I made. You won't. I must admit you're a convincing liar."

She ramped up the challenge, posting: "Do a lie-detector test together. Do an interview on #QueenRadio."