He said: “The serious allegations on the BBC’s Spotlight programme cannot be swept under the carpet.
“Robin Newton should immediately resign as the speaker of the Assembly and his position as an MLA is now in serious question.
“Mr Newton has been misleading the Assembly and the public since last year when the SDLP Deputy Leader, Nichola Mallon, first asked him to clarify his relationship with Charter NI.
“The DUP leader needs, very quickly, to respond to the Spotlight revelations.
“The public have every right to be angry – the last 10 years of government in Northern Ireland has brought us scandals in RHI, Red SKY, NAMA and now SIF.
“The Spotlight programme also contains huge questions for Sinn Féin – they cannot wash their hands of their role in all of this.
“As a party they were jointly responsible for the SIF funds and for every other decision which went through the Executive Office.
“They were jointly responsible for the channelling of funds to groups linked to the UDA.
“Therefore, they are jointly responsible for the corruption of Northern Ireland’s politics.
“This was their status quo and they were up to their necks in it,” added the Foyle MLA.