In Thailand for attending an Asia-Pacific summit, Bush said the US was in discussion with other countries involved in negotiations with North Korea, in an attempt to end the stalemate over the reclusive country's suspected nuclear programme.
"We have no intention of invading North Korea," Bush told reporters as he met Thai Prime Minister Thaksin Shinawatra.
"I have said as plainly as I can that we have no intention of invading North Korea," he said
But in the same breath he added, "we will not have a treaty, if that’s what you are asking. That’s off the table."
North Korea has long demanded a non-aggression guarantee from the US as an essential pre-requisite before it agrees to negotiate over its nuclear arsenal.
"We have no intention of invading North Korea"
The Central Intelligence Agency(CIA) believes it has produced at least one or two nuclear weapons.
The US president is expected to discuss North Korea when he meets Chinese President Hu Jintao later during the day.
"First of all what's important here is that the burden is on North Korea, not on America. North Korea must get rid of her nuclear ambitions. She must get rid of her weapons programmes, in a verifiable way, I might add," Bush said.
US Secretary of State Colin Powell said on Friday the US had drafted new ideas on security assurances to offer to North Korea in exchange for a promise to dismantle its nuclear weapons programme.