Beef, North Korea - and Elvis Presley - were among the topics discussed by the US and Japanese leaders in Washington on Thursday.
Junichiro Koizumi is among George Bush's closest allies
President George Bush thanked Japan for moving to lift a ban on US beef imports over fears of "mad cow disease".
Prime Minister Junichiro Koizumi warned North Korea "pressures" would be applied if it goes ahead with test-firing a long-range missile.
Mr Bush thanked Mr Koizumi for Japan's support in Iraq and Afghanistan.
It was dubbed a "sayonara summit", as Mr Koizumi steps down in September ("sayonara" means goodbye in Japanese).
The joint news conference was dominated by questions to Mr Bush on the US Supreme Court's ruling on military tribunals at the US base at Guantanamo Bay, Cuba.
There were several expressions of the two leaders' personal esteem for each other.
Mr Koizumi said there had been no other world leader with whom he had shared the same "heart-to-heart" friendship and trust.
Mr Bush hailed Japan's decision to restore beef imports from the US - first banned in December 2003 after a cow with bovine spongiform encephalopathy (BSE), also known as mad cow disease, was discovered in Washington state.
The issue had provoked threats of trade sanctions by the US against one of its closest allies.
But this month Tokyo decided to lift the ban, pending inspections of US meat processing plants, and during Thursday's news conference Mr Koizumi revealed he had eaten US beef the night before.
Mr Bush also said he and Mr Koizumi were concerned about "unacceptable" North Korean plans to test-fire a long-range missile thought to have Alaska within its range.
Mr Bush said they did not know what would be loaded on to the missile, and where North Korea intended to aim it. He said North Korea's leader Kim Jong-il had an obligation to provide a "full briefing" to those concerned on his intentions.
Mr Koizumi warned the North it would face "various pressures" if it went ahead with the test, without elaborating.
On Friday, Mr Koizumi will be treated to a tour of the home of his musical hero, Elvis Presley, escorted by Mr Bush.
"Officially he's here to see the president, but I know the highlight of his trip will be paying his respects to 'the King'," joked Mr Bush.
And Mr Koizumi ended the conference by saying, "Thank you very much, American people, for Love Me Tender."