JAPAN'S Finance Minister, trying to defend a shambolic performance just after a top-tier international summit, yesterday denied he had been drunk, blaming cold medicine in seeking to explain why he had slurred his words, was confused over basic numbers and appeared drowsy at a press conference.

Mr Shoichi Nakagawa's performance after the weekend Group of Seven (G-7) meeting in Rome came under fire from the media and the opposition called for him to be sacked.

However, Prime Minister Taro Aso has rejected these calls.

"Something like a joint statement was issued," he told reporters as he appeared to struggle to keep his eyes open.

"Interest rates, uh, set by the BoJ are between zero and 0.25 per cent and are very low," he said to the visible dismay of the central-bank chief sitting next to him.

The BoJ's target rate is now 0.1 per cent.

Mr Nakagawa also mistakenly thought a question for Mr Shirakawa was directed at himself.

One tabloid headline blared "Drunk!?". TV commentators said they worried about not just the health of the economy, but also that of the Finance Minister, who is reputedly a hard drinker.

"This should deserve immediate firing. It's a scandalous act," said the secretary-general of the main opposition Democratic Party, Yukio Hatoyama, adding that the "damage to our national interest is immeasurable".

But Mr Nakagawa denied he was drunk or nursing a hangover.

"I had a cold. Honestly, the cold medicine kicked in too much," he told reporters yesterday.

"I did not drink before the G-7," he added, sniffing loudly.

To be more exact, he said he drank alcohol and also took medicine on his flight to Rome, and that the combination may have had a bad effect.

"I drank wine at a party the previous day but I didn't drink before the news conference," he said.

He then suggested that he may have taken too much medicine: "That is the fact and I am sorry about it."

The flap was not something that the already deeply-unpopular government needed.

Still, Mr Nakagawa later said Mr Aso had asked him to stay on in his job after the two men met to discuss the G-7 meeting.

Chief Cabinet Secretary Takeo Kawamura, the top government spokesman, had said what happened in Rome was "extremely regrettable", while noting the minister had apologised.

Mr Nakagawa's bungling came as one TV poll found that support for the Aso government had plunged below 10 per cent. -AGENCE FRANCE-PRESSE