Japanese Prime Minister Shinzo Abe has declined to say if he nominated US President Donald Trump for the Nobel Peace Prize.
Mr Trump's assertion on Friday that Mr Abe had nominated him for the honour and sent him a copy of the letter has led to criticism in Japan.
Questioned in parliament about reports he had done so, Mr Abe said: "In light of the Nobel Committee's policy of not disclosing recommenders and nominees for 50 years, I decline to comment."
However, neither the prime minister nor his spokesman denied Mr Trump's comment.
"I never said I didn't" nominate him, Mr Abe said in response to a follow-up question by Yuichiro Tamaki, a politician for the opposition Democratic Party for the People.
Mr Tamaki said in a tweet that given the lack of progress on various issues with North Korea that he was concerned such a nomination would "send the wrong message to North Korea and the rest of international society".
In responding to Mr Tamaki's questions in parliament, Mr Abe praised Mr Trump, saying he "has been decisively responding towards resolving North Korea's nuclear and missile problems, and last year he held historic US-North Korea summit talks".
Mr Abe added that Mr Trump had also passed on to North Korean leader Kim Jong Un Japan's own concerns about abductions of Japanese citizens by Pyongyang, saying "he and the entire White House also actively cooperated in resolving the issue".
"I highly praise President Trump's leadership," Mr Abe said.
Mr Trump's claim that Mr Abe had sent him a "beautiful copy" of a letter sent to the Nobel Committee could not be immediately verified.
The government's top spokesman, Yoshihide Suga, echoed Mr Abe's remarks in refusing further comment.
The Japanese newspaper Asahi Shimbun reported on Sunday, citing unnamed government sources, that Mr Abe had nominated Mr Trump at the president's request.
Former president Barack Obama was awarded the Nobel Peace Prize in 2009, his first year in office, for laying out the US commitment to "seek the peace and security of a world without nuclear weapons".
Mr Trump complained on Friday that Mr Obama was there "for about 15 seconds" before he was awarded the prize.
The deadline each year for nominations is midnight on January 31. According to the website of the Nobel Committee, there are 304 candidates for the Nobel Peace Prize for 2019. It said 219 are individuals and 85 are organisations.