Fawzi Barhoum, the Hamas spokesman said the money for Mahmoud Abbas and the security adviser, Mohammad Dahlan, was meant to fuel divisions among Palestinians and undercut the unity government formed by the ruling Hamas Islamists and Abbas's Fatah faction.
The $59.36 million security programme was scaled back from an initial $86.4 million after Abbas joined forces with Hamas in a bid to end factional warfare and ease a Western aid boycott.
It is unclear whether the revised package will win US congressional backing.
A Western boycott on diplomatic contacts has eased since the appointment of non-Hamas ministers to the government, but economic sanctions remain in place and the new coalition is already showing signs of internal strain.
The bulk of the new security package - $43.4 million - will be used to "transform and strengthen the Palestinian Authority presidential guard".
The sum includes $14.5 million for "basic and advanced training", $23 million for non-lethal equipment, $2.9 million to upgrade the guard's facilities and $3 million to provide "capacity building and technical assistance" to Dahlan's office.
The aid also includes $16 million to bolster security at the Karni crossing.
The programme will be led by the US security coordinator between Israel and the Palestinians, US Lieutenant-General Keith Dayton.
The presidential guard's training will not be conducted directly by US government personnel.
Included in the non-security funding is $1.7 million to help "pre-position" the US Agency for International Development "to respond with support for any future electoral events in the West Bank and Gaza".
Abbas's long-running threat to call elections faded after the unity government was formed.
Other US programmes include $4.5 million to help the Palestinian Monetary Authority set up a financial intelligence unit to "counter terrorist financing and money-laundering".