Prime Minister Malcolm Turnbull has been accused of blackmail after he vowed to dissolve both houses of parliament if the Senate rejects laws to tackle union corruption.
Parliament will be recalled on April 18 and given three weeks to deal with two government bills previously rejected by the Senate.
If senators reject, amend or fail to pass the bills to restore the building and construction watchdog and impose higher penalties for union corruption, there will be a double-dissolution election on July 2.
"I feel as though it is a threat," independent senator Glenn Lazarus told reporters in Brisbane.
"But I'm not going to be blackmailed or bullied into making a decision."
Fellow independent Nick Xenophon warned the ugly scenes witnessed in the Senate last week following a marathon fiery debate on changes to the way Australians elect senators would be nothing compared to what's to come.
"If last week was pretty ugly, this debate will be even uglier," he said.
"It's a very nifty and cunning manoeuvre on the part of the PM but I expect it's going to cause fireworks in the Senate."
With Labor and the Greens opposed to the legislation, the government needs the support of six crossbenchers.
So far, only Family First senator Bob Day has flagged his support.
Others including Senator Xenophon, Senator Lazarus, Dio Wang and David Leyonhjelm will only back the laws if amendments are made.
"I want to sleep at night and if I voted for the ABCC in its current form, I wouldn't be able to," Senator Lazarus said, arguing he would only back the building industry watchdog if it was broadened to a national corruption body.
Senator Day said Mr Turnbull had called him on Monday morning to ask him to support the legislation and try to get other crossbenchers on board.
He said he almost convinced his colleagues to back the changes last time, but wasn't confident the angry cross bench could be persuaded following last week's Senate voting changes.
"Had the government been a little bit more patient last year, it perhaps could've got them over the line," he told Sky News.
Senator Day will support the bills but won't be lobbying his colleagues.
"I don't see any point in me trying to lobby them ... the events of last week put paid to that sort of action."
He described Mr Turnbull's announcement as "too clever by half".
"They won't get the ABCC through and they won't clear out the minor parties and independents from the Senate - they'll get neither of the things they are after."
Senator Xenophon said it was now up to the Senate to determine what hours it wanted to sit.
He warned the prime minister's move was a twin-edged sword - a double-dissolution election makes it easier for minor parties and independents to get elected than a regular half-Senate election.
"These are certainly high stakes and either the prime minister will succeed or it will spectacularly backfire."
Senator Leyonhjelm said the ABCC laws could be passed if the government negotiated in good faith but warned the cross bench was extremely angry over changes to Senate voting.
"If it's a take-it-or-leave-it attitude, then I'm going to leave it," Senator Leyonhjelm said.
