Sinn Fein are "reverting to type" by blaming the British Government for the cuts imposed on Stormont, Ulster Unionist leader Tom Elliott has said.
Deputy First Minister Martin McGuinness had accused the senior unionist, whose party was formerly in an electoral pact with the Conservatives, of failing to challenge Prime Minister David Cameron over the cuts.
But Mr Elliott said Sinn Fein had failed to see the wider international causes of the economic crisis, which he said had made cuts "an unwelcome fact of life".
Earlier this week the Ulster Unionists and the SDLP voted against a new Assembly budget which managed the £4 billion in cuts imposed by the Conservative-led Government.
Mr McGuinness, whose party backed the package with the support of the DUP and Alliance, said the UUP had failed to challenge the Tories on the cuts, while he described SDLP efforts to oppose the measures at Westminster as "weak-kneed".
But Mr Elliott said: "Martin McGuinness resorts to republican type in seeking to blame the British for all the ills of society, yet expecting them to keep sending cheques across to Ireland - north and south - without complaint.
"The coalition Government at Westminster is seeking to tackle the mountain of debt which the Labour administration left us. Even the Labour Party accepted that public spending cuts were inevitable had they won the election.
"The entire United Kingdom is facing public spending reductions and no region of the UK can expect to be exempt from this. Cuts are an unwelcome fact of life in Northern Ireland, Wales, Scotland, the north-east of England, the north-west of England and elsewhere."
Mr Elliott added: "Similar cuts are also being applied in Greece, Portugal and the Republic of Ireland. Possibly Martin McGuinness believes these are the result of Tory cuts, anything is possible given Sinn Fein's economic illiteracy.
"Martin McGuinness is complaining bitterly that the settlement which Northern Ireland received from Westminster is insufficient. He should be thankful that Unionists have thwarted his stated aim of a united Ireland, because the level of cuts in that scenario would be of an even worse scale."