Former foreign minister Alexander Downer has lashed out against state border closures.

South Australia, Western Australia, Queensland, Tasmania and the Northern Territory have kept their borders shut to interstate visitors to prevent the spread of COVID-19.

Queensland Senator Pauline Hanson is launching a legal challenge in the High Court, as is former MP Clive Palmer.

Each allege the closures of Queensland and WA borders respectively are unconstitutional, because they restrict trade.

Australia’s longest-serving foreign minister and former High Commissioner to the United Kingdom agrees, telling Deborah Knight the premiers need to listen to federal medical advice.

“There’s no medical basis for it,” Mr Downer said.

“There’s no health advice saying that they should be shut.

“I’m the grandson of one of the architects of the federal Constitution, and this idea of closing the borders … doesn’t sit well with me at all.

“We are one country, and we should have no restrictions on people moving between our states.”

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