The decision of the parliament's culture committee to ask for the appearances follows news that Scottish Opera is more than �1m in the red.

The committee will begin by questioning Junior Culture Minister Rhona Brankin.

Third debt crisis

It will then question representatives of Scottish Opera, Scottish Ballet and the Royal Scottish National Orchestra about the way those organisations are funded and how they manage their finances.

Representatives of the Musicians Union and Equity are also expected to be called to give evidence.

The company is seeking more money

More than �1 from every man, woman and child in Scotland goes in tax to keep Scottish Opera in business.

With its annual audience numbering around 100,000, the subsidy amounts to �55 per performance for each person watching the performances.

For the third time in recent years, Scottish Opera is in deep financial crisis and is asking for more money.

But the Scottish Arts Council, which has received a request for money from the national company, has said a proposed merger with Scottish Ballet cannot go ahead until the situation has been resolved.

Merger proposal

Arts Minister Sam Galbraith has expressed concern over the situation and representatives of both organisations have been summoned to talks with the government this week.

Arts council chairman, Magnus Linklater, said the problem would impede the merger proposal but expressed the hope that Scottish Opera could reach a resolution.

The merger has been seen as a means of consolidating the position of both companies after previous periods of financial instability.

Funding problems

Scottish Opera's general manager Ruth Mackenzie, who would have overseen the merged company, resigned her post earlier this year and blamed irreconcilable differences with the board of Scottish Ballet.

The Scottish National's Party's culture spokesman, Mike Russell MSP, said: "The whole point of the impending merger between Scottish Opera and Scottish Ballet was to find a long-term solution to the funding problems experienced by these national companies.