US President Donald Trump has proposed a military budget that is the largest since 2011 and focused on beefing up the country’s nuclear defences and countering the growing strength of China and Russia.

The proposal, part of Trump’s budget request for the US government, would provide the Pentagon $US617 billion ($787 billion) and an additional $US69 billion to fund ongoing wars in fiscal year 2019.

That is $US74 billion more than in the budget for the previous fiscal year.

Critics, however, say that the proposed spending increase falls short of what Trump had promised during the 2016 presidential campaign, when he frequently depicted the US military as underfunded.

The budget documents specifically highlighted “reversing the erosion of the US military advantage in relation to China and Russia,” which was a focal point of the National Defence Strategy unveiled by Defence Secretary Jim Mattis in January.

Funds for the maintenance of the US nuclear arsenal also increased.

The budget request must be passed by Congress, which controls federal purse strings and rarely enacts presidential budgets.

The Pentagon’s budget request earmarks $US10.7 billion for the purchase of 77 F-35 fighter jets made by Lockheed Martin Co as well as $US2 billion to purchase 24 Boeing Co F-18 Super Hornets.

The budget request for the Missile Defense Agency (MDA), the agency tasked with protecting the country from missile attacks, was $US9.9 billion, which is up from the $US7.8 billion funding request for fiscal 2018.

The US Army’s request earmarks funds to modernize 135 Abrams tanks. The 2018 budget requested the modernisation of 56 of the General Dynamics-made vehicles.