Oireachtas committees should consider obstructing the passing of legislation and the estimates process if senior Government officials refuse to answer questions before them, according to Sinn Féin's Pearse Doherty. 

Deputy Doherty, who is a member of the Finance Committee, strongly criticised the refusal by the Secretary General of the Department of Public Expenditure and Reform, Robert Watt, to answer questions about cost overruns at the National Children's Hospital.

Mr Doherty said the committee should "up the ante" in its dealings with the Government: "Why should we be facilitating discussing the estimates of the department if we have the general secretary not willing to come before and discuss a major scandal in this state?" he asked. 

Mr Doherty said the Finance Committee respects and facilitates the Finance Minister and officials when they request to come before it to discuss legislation or spending estimates. But he said it has to be a "two-way street." 

Mr Watt said he will answer to the Dáil's Public Accounts Committee, but Mr Doherty pointed out that the heads of government departments are answerable to relevant committees and his department "is the sanctioning and authorising department in relation to this project." 

He said: "In my view - and I will talk to the Committee later on - we need to up the ante in relation to this issue. A general secretary should be willing to appear before a committee of Oireachtas members - who are accountable to the public - and answer questions in an area where they have responsibility."