Shares in Banca Carige failed to start trading at the open after the top investor in the troubled Italian lender put its future into question by blocking a key 400 million euro ($455 million) new share issue.

The cash call was part of a rescue financed by Italian lenders to prevent a banking crisis at a time when the industry is already struggling with higher funding costs and shrinking capital buffers due to the policies of Rome's anti-European government.

By 0807 GMT shares in Carige were indicated at 0.0014 euros down from 0.0016 euros on Friday. Italy's banking index lost 0.4 percent.