U.S. Defense Secretary Leon Panetta has arrived in Seoul on the final leg of an Asian tour aimed in part at reassuring allies of the United States' commitment to the region.

The newly installed secretary is to meet later Wednesday with some of the 28,500 U.S. troops in South Korea. He will attend meetings Thursday and Friday with senior government and defense officials.

Writing Wednesday in a major South Korean newspaper, Panetta reaffirmed the American commitment to South Korea's defense. He said in the Chosun Ilbo that the U.S. and South Korean militaries stand prepared to defeat North Korea should it ever force war upon the allies.

Panetta has delivered a similar message throughout his tour, which included stops in Indonesia and Japan.

On his arrival in Japan on Monday, he promised the United States will not reduce its military presence in East Asia in spite of coming budget cuts at home.

Panetta's Tokyo talks also dealt with controversial plans to transfer a key U.S. military base in Okinawa to another location on the island. Japanese Defense Minister Yasuo Ichikawa told him Tuesday that Japan will complete an environmental assessment on the plan by the end of this year.

The two officials also reaffirmed the importance of the U.S.-Japan security alliance as a cornerstone of peace and stability in the Asia-Pacific region.

Panetta is making his first visit to Asia since he moved from CIA director to defense secretary in July.