Nippon Telegraph and Telephone Corp. will launch inspections to check whether there are human rights violations at its major suppliers from fiscal 2022 to root out unethical practices from its supply chains, company sources said Tuesday.

The telecom giant is planning to visit between 40 and 50 major suppliers a year in Japan and abroad to check whether they are engaged in such practices, including forced and child labor, the sources said.

The parent of group companies such as NTT Docomo Inc. and NTT Data Corp. will consider tough consequences, such as terminating business deals, depending on the outcome of the inspections, which are expected to begin in the business year starting April, they said.