The government is easing the pressure to refer Labor MP Susan Lamb to the high court over her citizenship – the prime minister has signalled to colleagues that the forced referral threat is, for now, off the table.

Malcolm Turnbull has not ruled out returning to the so-called “nuclear option”, where the government would use its numbers in the lower house to refer Lamb to the court without Labor’s co-operation, in the future.

The leader of the house, Christopher Pyne, had publicly confirmed before parliament resumed for 2018 that the government was considering forcing Lamb’s referral to the high court.

Coalition to pursue Susan Lamb over citizenship despite tearful speech Read more

However, after discussions with colleagues – with an interest in the Coalition’s electoral fortunes in Queensland, where a Liberal win in Lamb’s marginal seat of Longman is by no means guaranteed – Turnbull has privately indicated the government will not be pursuing a forced referral.

Instead, it intends to maintain the pressure on Bill Shorten to refer the MP himself, the narrative shaped around it being a “test” for the Labor leader.

Sources familiar with the prime minister’s thinking said an electoral loss in Longman could potentially cause internal problems, with Queensland Coalition MPs already nervous about their re-election prospects.



Play Video 1:40 Susan Lamb makes emotional statement about citizenship – video

There are also concerns that public sympathy in the electorate would increase Lamb’s margin in the seat, which she now holds by less than 1 per cent.

Lamb delivered an emotional speech to parliament on Wednesday, where she explained that the estrangement from her mother, who left her when she was six-years-old, and the death of her father, meant she was unable to provide her parents’ marriage certificate, when renouncing her British citizenship by descent.

She said she had been advised that without the permission of her living parent, she would be unable to receive the document.

The government says that has left her, by the “black letter of the law”, open to referral, claiming she is still a dual citizen, and as recently as Wednesday it indicated it would continue the campaign to have her case sent to the court.

Labor maintains that Lamb took all reasonable steps and has pointed to a letter it says she received from the UK Home Office, which said it was unable to determine if she was a British citizen.

Under Queensland law, when a parent is still alive, permission must be obtained from that parent in order to access birth, death and marriage certificates. The registry has since clarified that in extenuating circumstances, discretion can be applied by the registrar. Labor has not said if Lamb attempted to apply for an exception.

It is understood that the Queensland government is discussing changes to the registry rules to ensure the situation does not repeat itself.