Prime Minister Malcolm Turnbull has defended his Government's overhaul of Senate voting laws, saying the views of the new crossbench need to be respected.

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Mr Turnbull's Government will be dealing with an Upper House crossbench of 20, including nine Greens senators and four One Nation senators.

Among them is One Nation senator-elect Malcolm Roberts, who has called for an inquiry into the CSIRO and has vowed to force a change to the Racial Discrimination Act.

Mr Turnbull said his views should be respected, telling 3AW that "every single member of the Senate, regardless of what their views are, has been elected by the Australian people".

"That's why their views must be listened to, respected," he said.

Mr Turnbull defended his Government's changes to the way senators are elected, saying it "absolutely worked".

He said he would be meeting with all crossbenchers and had already held a "constructive" meeting with One Nation Senator-elect Pauline Hanson.

"I respect her, I respect her election," he said.

"Half a million Australians voted for her. I've had a very constructive meeting with her … the vast bulk of the subjects we discussed had nothing to do with migration.

"She does have views on migration that I don't share, that the Government doesn't share."

'Watch out for 18C': Racial Discrimination Act back on table

The Government will need 39 votes to pass legislation in the Upper House.

The Coalition has 30 senators, leaving them to negotiate with the crossbench to pass measures such as its industrial relations reform.

Nick Xenophon Team senator Stirling Griff said he and his two colleagues were "almost there" in supporting the ABCC legislation.

Senator Griff told Radio National that the party would support it, "subject to some minor amendments".

But the Government may have to negotiate on banking measures, with Senator Griff voicing support for a royal commission into the sector.

"If we can have a royal commission into union corruption, we can have one into banking," he said.

Senator-elect Roberts joined Senator Griff on air, saying that he would need to see the detail of the Government's banking measures before making any "informed comment".

He did voice support for changes to the Racial Discrimination Act, a push which Justice Party Senator Derryn Hinch also backs.

"Watch out for 18C (section of Racial Discrimination Act), because that is going to be right back on the table," he said.

"I want to scrap it."

The pair said they would support establishing a plebiscite on same-sex marriage if it was the quickest way to resolve the issue.

Senator-elect Roberts said it was "really necessary for the people to have their say".

Senator Hinch said he wanted Parliament to deal with the issue, but "if a plebiscite is the only way to get this through, then you'd probably have to go with the plebiscite".