The four-member panel voted unanimously to pursue the probe into imports from Malaysia, Thailand, Cambodia and Vietnam. The brief meeting was broadcast online.

The vote was the latest step in a trade petition brought by a group of U.S. solar panel manufacturers in April. Hanwha Qcells, First Solar (NASDAQ:FSLR) and others accuse Chinese companies with factories in the four nations of flooding the U.S. market with panels priced below their cost of production.

If the case is successful, companies that import panels to install on rooftops or build large-scale solar power plants could face higher prices within months.

The ITC's role in the case is to determine if the domestic industry is being harmed by imports. The U.S. Commerce Department would decide the level of duties that could be imposed.