Crossbench senator Derryn Hinch has become the latest potential victim of a worsening citizenship saga after admitting he has links to the United States that could disqualify him.

Senator Hinch has admitted he still holds a social security card from when he lived in New York that could mean he is ineligible to sit in the Senate.

Speaking to media from north Queensland shortly before boarding a flight to Victoria, Senator Hinch said he planned to refer himself to the High Court when Parliament resumed on Monday to clear up the issue, making him the eighth MP to do so.

But others within the government have questioned whether the referral would be accepted, given Senator Hinch does not hold and has never held United States citizenship, or even a green card, and social security numbers are issued as a matter of course without any attached citizenship benefits.