PRIME Minister Kevin Rudd says the Opposition should drop its negative attitude and support the passage of the Budget through the Senate.

The challenge comes as Opposition Leader Malcolm Turnbull prepares for his official Budget reply tonight after yesterday suggesting he could have possibly budgeted for a surplus.

The Government has defended its $58-billion deficit in its post-Budget sales blitz, which descended into a slanging match over whether debt would be lower under Labor or a Coalition government.

Labor has received both praise and criticism for its second Budget and the Opposition has laid the blame squarely at the feet of the Government.

It has accused it of reckless spending, saying it has no trust in the Government's forecasts predicting economic growth would return in two years and the Budget will be back in surplus in six years.