Sen. Bernie Sanders, I-Vt., wants to force lawmakers to pay for their proposed war and defense spending, and he plans next week to introduce a "war tax" amendment to the GOP budget that would require millionaires to pay a tax to finance U.S. military operations.

House GOP leaders agreed earlier this week to add an additional $36 billion in defense spending to their annual budget resolution that comes up for vote next week, reported USA Today.

The increase prompted Sanders, a potential 2016 presidential candidate and ranking Democratic member on the Senate Budget Committee, to take action.

"Republicans have been telling us for years that because of high deficits we have to cut Social Security, Medicare, Medicaid, education, nutrition and virtually every program that benefits working families. On the other hand, their concerns about deficits seem to disappear when it comes to war and defense spending," Sanders wrote in a press release published Friday.

"The Republicans took us into protracted wars in Afghanistan and Iraq - and ran up our national debt by trillions because they chose not to pay for those wars. Instead, they put the cost of those wars on our national credit card. Yesterday, Republicans on the Senate Budget Committee voted for an increase of $38 billion in defense spending - all added to the deficit."

Democrats plan to use next week's budget "vote-a-rama" to send a message about the Republican spending plan. Senators have the opportunity to propose an unlimited amount of amendments to the GOP budget plan, and Sanders' "war tax" will be one of the first he introduces, according to The Hill.

The proposed increase in defense spending would bring the Pentagon's war funding account, referred to as the overseas contingency operations (OCO) account, to $96 billion.

The account has funded the Iraq and Afghanistan wars and now helps pay for the ongoing fight against the Islamic State group in Iraq and Syria. OCO has little oversight and falls outside the Defense Department's base budget. Because OCO isn't affected by sequestration budget caps, Republicans are depending on the account to increase military spending - a practice Sanders called a "gimmick," according to The Hill.

"The Republican Party is going to have to end their hypocrisy with regard to deficits and the national debt. They are going to have to be honest with the American people. Wars are enormously expensive, not only in terms of human life and suffering, but in terms of the budget," Sanders wrote.

"If the Republicans want another war in the Middle East, they are going to have to tell the American people how much it will cost them and how it will be paid for. This is an issue that I and others intend to raise forcefully during this week's debate on the Senate floor. I strongly expect that there will be amendments demanding that Republicans tell us how they will pay for another war."