Progress in curbing global warming now rests on the shoulders of the United States says United Nations (UN) General Secretary Ban Ki-moon.

"All the world is now looking to the leadership of the United States and President Obama," Ban said in an interview with the Seattle Times.

Currently on a two-day visit to Seattle, Ban said that U.S. leadership is "crucial" for reaching success at the U.N.'s December meeting in Copenhagen.

"An engaged United States can lead the world to seal a deal to combat climate change in Copenhagen," Ban wrote in an op-ed piece in the New York Times. "An indecisive or insufficiently engaged United States will cause unnecessary - and ultimately unaffordable - delay in concrete strategies and policies to beat this looming challenge."

While expressing his high expectations of the country, Ban also applauded recent efforts from the U.S. government, including those of Senators John Kerry (D-Mass.) and Lindsey Graham (R-S.C.), authors of a bipartisan energy bill now being run through Congress. The general secretary also complimented President Obama's involvement in the U.N.'s September climate change summit in New York, which he said sent a, "clear message of solidarity and commitment."

Ban's remarks come with less than 50 days remaining until the December meeting, a gathering that U.K. Prime Minister Gordon Brown said will, "set the course for the next few decades."

For Ban, reaching a "successful deal" at Copenhagen means reaching one that is financed, includes "equitable governance structure," and is one that provides "comprehensive support" for areas most affected by the climate change crisis.

Ban also stressed the need for all countries to do their, "utmost to reduce emissions from all major sources, including…deforestation and emissions from shipping and aviation."

"The elements of a deal are on the table," Ban wrote. "All we require to put them in place is political will."

"We need to step back from narrow national interest and engage in frank and constructive discussion in a spirit of global common cause."