Park made the remark during a rare trip to the heavily fortified border with the North.
North Korea has routinely pressed South Korea to honor agreements reached at two previous summits in 2000 and 2007 and made Seoul's implementation of them a key condition for better ties.
The deals have been in limbo as relations between the two Koreas have been at one of the worst levels in decades after current President Lee Myung-bak took office in early 2008 with a harder-line approach to Pyongyang.
Park said that previous inter-Korean promises "should be kept," as part of efforts to build confidence between the two divided countries.
Still, she said that deals reached at the 2007 summit should "win a parliamentary endorsement" before being carried out as their implementation requires a lot of money and involvement of private companies.
The first summit paved the way for the two Koreas to ease military tensions and begin economic cooperation after decades of hostilities.
In 2007, the leaders of the two Koreas also produced a deal calling for the South's massive investment in the North's key industrial sectors, including shipbuilding and tourism. South Korea is the No. 1 shipbuilding nation in the world.
Park's rare trip to the border came more than an hour after North Korea announced that its young leader Kim Jong-un had been awarded the title of marshal in the latest promotion following the December death of his father, long-time leader Kim Jong-il.