OTTAWA - Thomas Mulcair says Prime Minister Stephen Harper will have a fight on his hands if tomorrow's budget ignores job creation in favour of cuts to services, health care and pensions.

The freshly minted NDP leader is taking part in his first formal Parliament Hill caucus meeting after winning the leadership on the weekend.

In a rah-rah speech to his MPs, he says the NDP has to roll up its sleeves and stand firm against Harper and Conservative policies.

He says the business of defeating Harper starts now and will culminate in a New Democrat government in the next election.

Mulcair portrays the prime minister as an ideologue whose policies will help the well-connected and hurt the middle class.

He says the NDP's job is to fight that.