The circumstances in which Venezuela assumed Mercosur's full membership shortly after Paraguay's suspension remain as murky as when the episode began with a political crisis in Asuncion in June 2012.
Paraguayan opposition to Venezuela entering Mercosur was the last stumbling block in the way of Chavez's ambition to play a major role in Mercosur. But on June 22 the country's Senate voted to impeach President Fernando Lugo, prompting his resignation.
Mercosur reacted by calling Lugo's impeachment a constitutional coup. The political and economic group suspended founding member Paraguay from its ranks and invited Venezuela to join, which Caracas promptly did.
The speedy musical chairs that isolated Paraguay became part of a regional diplomatic effort by Argentina, Brazil and Uruguay to have the country banned from other forums, including the Organization of American States. The ploy didn't work but created ill will between Paraguay's incoming caretaker President Federico Franco and the rest of Mercosur.
Chavez's death March 5 raised hopes Mercosur and Paraguay could erase bitter memories of 2012 and resume normal ties.
Mercosur interstate trade has suffered as the quarrel continues. Paraguay's estranged partners have made repeated attempts to heal differences. Having made grand gestures against Paraguay last year, leaders of Argentina, Brazil and Uruguay have struggled to row back on their pronouncements without losing face.
Paraguay this week made clear it won't accept anything short of full restoration of its Mercosur membership and, through that restoration, its right to preside over the next group summit.
Venezuela is set to preside over the summit in June. Who'll represent Venezuela at the summit in Uruguay isn't clear, as Acting President Nicolas Maduro is one of several candidates in that country's April 14 election.
Paraguay's presidential election is to take place April 21. Franco isn't a candidate and Horacio Cartes of the center-right Colorado Party is favored to win.
Whatever the outcome in the two elections in Paraguay and Venezuela, divisions caused by last year's events are unlikely to be resolved soon.
In January Paraguay condemned Mercosur's incorporation of Bolivia as a new member and denounced Uruguay for taking presidency of the group for the current six-month term which, it said, violated rules on the rotating leadership.
Paraguayan Foreign Minister Jose Felix Fernandez Estigarribia said the country wouldn't flinch from its position that Paraguay should hold Mercosur's presidency in the next rotation beginning June.
Maduro said he expects Venezuela to lead the summit.
"Venezuela according to our criteria still has not been legally incorporated to Mercosur, since it is violating the original treaties which refer to the constitutions of the group," Fernandez Estigarribia said.
He said Paraguay's April elections will restore the country to full democracy, a fact recognized by the OAS and EU partners. Paraguay's new government will take office Aug. 15.