Park Geun-Hye vowed a “clean” government and a tough stance on national security during her inauguration as South Korea’s first female president on Monday.

Park took the oath of office in front of tens of thousands of people in Seoul where she promised “a clean, transparent and competent government” and an era of economic revival.

“The Koreans have made a great history of achieving both industrialization and democratization with their strong ‘can do’ spirit,” Park said in her inauguration speech.

“I will open a new era of hope, which will enable all the public to enjoy the benefits of economic development.”

Park said that “trust-building” was needed to tackled the “extremely serious” security situation in the Korean Peninsula. Park also urged North Korea to abandon its nuclear programme and vowed to address threats from Pyongyang.

“North Korea’s recent nuclear test is a challenge to the survival and future of the Korean people, and there should be no mistake that the biggest mistake will be none other than North Korea itself,” Park said, adding that “trust-building” can be met through dialogue and “honoring promises that have already been made.”

But speculations that she will be unable to follow through her promises have plagued Park since elections, faced with the country’s sluggish economic growth, rapidly aging population and widening wealth gap, reports the Financial Times.