Defence spending to achieve GDP benchmark

Defence spending will hit a target of two per cent of GDP this financial year, the budget confirms. (AAP)

Australia's Defence spending will hit two per cent of gross domestic product this financial year, realising a long-term coalition goal.

Prime Minister Scott Morrison has promised to lift the Defence budget to two per cent of gross domestic product in the 2020/21 financial year.

Tuesday's federal budget confirms the mark will be achieved, with the government giving Defence $270 billion over the next decade - up from the $195 billion promised in 2016.

The government will also streamline the process for calling out Defence reservists to deal with natural disasters and other emergencies.