President Donald Trump will propose deep cuts for foreign aid and environmental protection and a steep increase in military spending in a budget plan to be released on Thursday, a congressional source said.

The budget plan for fiscal 2018 will call for cuts of 28 percent for the State Department, said the source, who was briefed on the outline of Trump's plans.

Trump is proposing a 10 percent increase in defense spending, equivalent to $54 billion, and a 6 percent increase in funding for homeland security, the source said.