LISBON, Portugal â Portugal's government could collapse Wednesday after opposition parties withdrew their support for another round of austerity policies aimed at averting a financial bailout. The expected defeat of the minority government's latest spending plans in a parliamentary vote will likely force its resignation and could stall national and European efforts to deal with the continent's protracted debt crisis. The vote comes on the eve of a two-day European Union summit where policymakers are hoping to take new steps to restore investor faith in the fiscal soundness of the 17-nation eurozone, including Portugal. Last year, both Greece and Ireland had to accept massive rescue packages after markets lost faith in their governments' efforts to deal with their debt burdens. The political tension fueled a rise in Portugal's borrowing rates, just as it is trying to cut spending.