A tweet aimed at Greens deputy leader Mehreen Faruqi was not based on her skin colour or ethnic origins, One Nation leader Pauline Hanson has argued in court.

Senator Faruqi has filed a Federal Court lawsuit over a September tweet by Senator Hanson who wrote that she should “pack (her) bags and piss off back to Pakistan”.

The tweet was in response to one sent by Senator Faruqi about the death of Queen Elizabeth II in which she wrote she could not mourn the passing of the leader of a “racist empire built on stolen lives, land and wealth of colonised peoples”.

Senator Faruqi is seeking $150,000 from Senator Hanson in the lawsuit, claiming the tweet breached the Racial Discrimination Act by being insulting, offensive, humiliating and intimidating to herself and those with Pakistani backgrounds.

Representing the Greens deputy leader in court on Thursday, barrister Jessie Taylor said “piss off back to Pakistan” was a variant on the phrase “go back to where you came from”.

This latter phrase had a “rich and harmful history as a racist epithet,” she told Justice Angus Stewart.

“Its effects are demonstrably harmful, demonstrably racist,” she said.

The tweet insulted and offended not only Senator Faruqi but also people of colour and those from migrant backgrounds, the judge heard.

“As a person who’s white, I find it offensive,” Ms Taylor said.

Senator Hanson’s barrister Sue Chrysanthou SC said her client denied the tweet was sent based on race, colour, national or ethnic origin.

She sought details of the Greens Senator’s case in proper pleadings, saying there was not enough information on how the tweet was allegedly discriminatory or what its effects were on her.

An application could also be made to elevate the case to the High Court, Ms Chrysanthou said, given it involved Australia’s implied constitutional freedom of political communication.

“This is not something that has ever been considered by the High Court,” the barrister said.

Future arguments about experts proposed to be called by Senator Faruqi were also flagged with Ms Chrysanthou saying that if the Greens deputy leader needed someone to give evidence about the allegedly racist epithet, it was not as widely known as she made it out to be.

Senator Faruqi will file her pleadings by June 15 while Senator Hanson will file her response by June 27.

The matter will next come before the Federal Court on June 29.