TOKYO • Fans of ageing Japanese boyband Smap are heaving sighs of relief at the news of the middle- aged heart-throbs averting a break-up.

Days after their agency said they were mulling over a split, the band carved out time on their weekly television show on Monday to apologise for causing anxiety and pledged to stay together - prompting so much joyful Internet chatter that Japan's Twitter network briefly crashed.

Wearing black suits, the five members bowed deeply before each offered short remarks.

Takuya Kimura, the most popular member and a megastar in Japan, explained that they hastily arranged to inject live speeches into their taped variety show SmapxSmap. He acknowledged that they had been on the verge of a "mid-air break-up".

Tsuyoshi Kusanagi said: "I am relieved that we five are again together right here."

The group's troubles were reportedly sparked by infighting between the agent in charge of Smap and other top managers at Johnny & Associates, the powerful talent agency behind Smap and numerous other boybands.

Last week's news of the possible break-up was greeted by saturation media coverage and despair on social media.

Yesterday, even Prime Minister Shinzo Abe hailed the announcement that the band would stay together.

"It was good that the group responded to the wishes of many fans and decided to continue," he told a parliamentary committee.

"Like in the world of politics, I assume there are various challenges for a group to keep on going for such a long period of time."

Formed in 1988, the group packed venues around Asia in their heyday and sang for Chinese leaders. They produce an annual revenue of 25 billion yen (S$304 million), weekly magazine Shukan Shincho reported.

AGENCE FRANCE-PRESSE, REUTERS