The Tokyo Stock Exchange's rare call for better capital efficiency has made Japanese companies scramble to compile action plans to avoid being seen as laggards, the chief of Mizuho Financial Group's trust banking unit said.

"There has been a sense of urgency brewing among companies" ahead of January, when the TSE starts publishing a list of companies that have disclosed action plans in line with its call to improve their use of capital, Kei Umeda, CEO of Mizuho Trust & Banking, said in an interview.

The TSE's reform push has been hailed by investors as a remedy to Japan's unusually high number of chronically undervalued stocks, but only 20% of companies listed on the top "prime" section had disclosed specific measures as of July.