Washington suspended military assistance in July to Bulgaria, Estonia, Latvia, Lithuania, Slovakia and Slovenia - along with many others - for failing to shield Americans from the International Criminal Court (ICC).
But in a memorandum issued by the White House on Friday, Bush said it was "important to the national interest of the United States" to waive the aid restrictions "for only certain specific projects that I have decided are needed" to support NATO's expansion as well as US military operations in Iraq and Afghanistan.
Free to help
The seeming gift comes at a price, however. The partial lifting of military aid restrictions frees up the six countries to provide their sponsor with greater support in its ongoing military operations worldwide.
Bulgaria, Estonia, Latvia, Lithuania and Slovakia have either deployed forces to Iraq or have committed to do so.
The ICC was set up last year to try war crimes and acts of genocide. The US says it fears its nationals overseas could be vulnerable to politically motivated charges.
Under former President Bill Clinton, the US signed the 1998 treaty creating the court, but the Bush administration later withdrew US backing.
Cherie speaks out
On the eve of Bush's visit to the UK this week, Cherie Booth, a prominent human rights lawyer and the wife of British Prime Minister Tony Blair, called for the US to join the ICC.
Speaking in Washington during a panel discussion on human rights and international law at Georgetown University, she said the US had a duty to set an example.
"It seems inconceivable that a state committed to the rule of law, such as the US, would refuse to investigate and prosecute its nationals should there be reliable evidence that they had been involved in international crimes," she said