More than two months after the Great East Japan Earthquake severed the supply chains of many manufacturers, a government survey on major businesses affected by the disaster signals they are likely to struggle for some time to come.

Less than 30 percent of businesses in the automobile, electronics and other processing industries who responded to the survey think they will be able to gain enough access to parts and other supplies by July, according to the Ministry of Economy, Trade and Industry survey.

The twin disasters that ravaged the northeast on March 11, coupled with the nuclear crisis, have exposed a major weakness among manufacturers — especially automakers. Their reliance on limited numbers of parts suppliers, a consequence of past consolidation efforts — could undermine their international competitiveness.