Providence Resources' technical director John O'Sullivan - the company's de-facto second in command to CEO Tony O'Reilly Jr - has left the company as part of a major downsizing of its operations and management structure.

Irish exploration company Petrel Resources has expressed confidence in attracting a major oil and gas company to buy into part of its licence portfolio off the west coast.

The ISEQ index of Irish shares was up 54.74 points to 6038.75 in morning trade today.