MSPs and staff were left unable to send e-mails or browse the web after telecom firm Cable & Wireless rerouted data traffic away from Princes Street due to the repair work on the tram tracks which got under way on Monday.
Lothians Labour MSP Kezia Dugdale said: “This must be the revenge of the trams on the Scottish Parliament.”
Meanwhile, a UK Government report showed the Capital’s tram project is set to cost nearly four times as much per mile as similar light rail schemes elsewhere in the UK.
Figures published by the Department for Transport said the average cost of building tramways in urban conurbations was £25m per mile. Current estimates for the Edinburgh project work out at nearly £100m per mile.