And as military relations continue to thaw, it was confirmed the Pentagon had accepted an invitation from Mr Key to send a group of marines to New Zealand to mark the 70th anniversary of their arrival during World War II.
At the top of Mr Key's agenda is the Trans Pacific Partnership (TPP) negotiations, aimed at creating a nine-country free trade zone including the US and New Zealand.
"We think it is critically important for confidence around the world to show that progress can be made on trade," Mr Key told reporters.
He conceded the TPP would not be concluded in time for an Asia-Pacific summit in November in Hawaii but said he would "like to see some sort of agreement signed that at least signifies that we're on the right track".
In a speech to the US Chamber of Commerce overnight (NZT) in Washington, Mr Key focused on drumming up enthusiasm for the TPP.
"The TPP represents something genuinely new and important," he said.
"It will establish a framework that will work for countries as diverse as Vietnam, New Zealand and the US...we see more value in a TPP that aims to modernise trade rules across a wide agenda in a region that has become the engine of global economic and trade growth."
Mr Key's meeting with President Obama will take place as the New Zealand dollar continues to reach record highs against the US dollar.
"I'll certainly be pointing out that the rising exchange rate is hurting our export sector and we have real concerns about that," Mr Key said before he left for Washington.
"It will be an opportunity to get a sense of what they are thinking is going to happen next."
Mr Key has acknowledged that President Obama may be preoccupied with the debt crisis -- Congress must raise the US$14.3 trillion ($16.58 trillion) limit on US borrowing by August 2 or the government will run out of money.
"Obviously the president is going to be very busy with these issues but the meeting lasts an hour," he said.
"I'm sure he's capable of focusing on that as well as the other big issues he's facing."
- NZPA
