WASHINGTON — The Obama administration today laid out a five-year, $2 billion military aid package for Pakistan as it pressed the Islamabad government to step up the fight against extremists there and in neighboring Afghanistan.

Secretary of State Hillary Rodham Clinton announced the plan at the end of the latest round U.S.-Pakistani strategic talks. The administration will ask Congress for $2 billion for Pakistan to purchase U.S.-made arms, ammunition and accessories from 2012 to 2016, Clinton said.

The new military aid replaces a similar but less valuable package that began in 2005 and expired on Oct. 1. It will complement $7.5 billion in civilian assistance the administration has already committed to Pakistan over five years, some of which has been diverted to help the country deal with devastating floods.

Although the exact terms of the deal are still being negotiated, the goal is to ramp up U.S. military aid to Pakistan incrementally over the five-year period.