Article published on the 2009-07-22 Latest update 2009-07-22 09:45 TU
Speaking on Thailand's Nation TV on Wednesday, Clinton insisted that the US “will still hold the door open" to negotiation while adding that "the nuclear clock is ticking".
Washington is also prepared to "upgrade the defence of our partners in the region," she said, adding that Iran must understand it will not be safer "if the United States extends a defence umbrella in the region."
Clinton later arrived in the Thai resort island of Phuket for Asia's largest annual security forum.
Talks with ministers from the Association of Southeast Asian Nations (Asean) are expected to be dominated by discussions about possible military co-operation between Myanmar and nuclear-armed North Korea.
Clinton touched down in Thailand on Tuesday after a five-day visit in India where she held talks over a new arms deal.
Clinton visit