Malcolm Turnbull has warned a Labor government would stop jobs and growth ‘dead in its tracks’, as he fired the starting gun on a July 2 election focused on the economy.

The Liberal-National coalition appears to have a slight edge over Labor ahead of an eight-week campaign ending in the first double dissolution election in three decades.

The prime minister said his government had a clear plan for jobs and growth which would be put at risk if voters put Labor leader Bill Shorten in The Lodge.

‘Look at the Labor Party – everything they are doing … is absolutely calculated to stop our economic progress in its tracks,’ Mr Turnbull said.

The Liberal leader said Australians should embrace the future ‘with confidence and with optimism, with self-belief and a clear plan’.

National security – from new spending on defence to border security – would also be a priority.

‘Unlike the Labor Party, Australians know we can be trusted to keep Australia safe and secure,’ Mr Turnbull said.

Mr Shorten said Labor would fight the election on creating jobs with ‘reasonable conditions’ and putting families and small business before big corporations.

It was a choice between Labor’s ‘positive plan for the future and three more years of dysfunction, dithering and disappointment’ under the coalition, which dumped Tony Abbott as leader last September.

‘This election is a choice about what sort of Australia that we want to live in,’ he said.

The prime minister indicated he would campaign on the issue that brought about the double dissolution election – restoration of the building industry watchdog and tougher penalties for union corruption.

If re-elected, the two parliamentary houses would meet in a joint session to pass the industrial laws.

‘It is a vital economic reform and critical to our continued success,’ Mr Turnbull said.

The coalition government currently holds 90 seats in the 150-seat House of Representatives while Labor has 55.

The government can afford to lose 14 seats, while Labor needs to win an extra 21 seats to claim victory.

The latest Galaxy poll puts the two parties at 50-50, with the coalition on 42 per cent of the primary vote (down three points on the 2013 result) and Labor on 36 per cent (up three points).

Such a poll result would bring about a hung parliament.

However, punters rate the coalition a 75 per cent chance of winning.

Mr Turnbull sought to neutralise Labor’s attack on corporate tax avoidance and his big business tax cut – the centrepiece of the coalition’s economic plan.

‘We believe in lower taxes, but it is not optional to pay them,’ Mr Turnbull said.

Greens leader Richard Di Natale – who is aiming to hold the balance of power after the full Senate election – said the coalition was failing Australia’s economic prosperity.

‘(Turnbull’s) silent on the biggest driver of new jobs of growth in Australia and that is the transition to the clean economy,’ Senator Di Natale said.

With the Greens polling 11 per cent of the primary vote, the minor party’s preferences will be crucial for Labor.