Pruaitch is part of the opposition grouping that has been in Vanimo in Sandaun Province for the past nine days after a mass crossing of the floor of parliament by government MPs, Radio New Zealand International reports.
The opposition had been seeking to hold a vote of no confidence next week but this was stymied by a government adjournment of parliament through to April next year. It is appealing that move by the government.
Pruaitch said the government's reliance on debt financing is "offensive to any rational thinking leader".
He said the government, of which he had been part until very recently, has taken the PNG economy on a "path of self-destruction".
The former minister said "the public have been given a false sense of progress with alluring slogans such as ‘Take back PNG' and promises to turn PNG into ‘the richest black Christian nation where no child is left behind' when, in reality, thousands of families are being forced into lives of poverty as jobs disappear and agricultural output shrinks".