Brazil’s vice-president, Michel Temer, must face impeachment proceedings, a supreme court judge ruled on Tuesday as senior lawmakers called for early elections to stem the country’s intensifying political crisis.

A congressional committee is debating whether to remove Workers party president Dilma Rousseff from office for breaking fiscal rules before her re-election in 2014. The impeachment battle has led to government paralysis and massive street demonstrations for and against what Rousseff and her allies are calling a “coup”.

Temer – a senior member of the Brazilian Democratic Movement party – is poised to replace the president if she is removed. But with the latest ruling, he is also at risk of being forced out.

Justice Marco Aurélio Mello said the lower house must discuss the vice-president’s fate because he is accused of the same charges as Rousseff. The judgment could yet be appealed, but it appears to be a boost for the beleaguered president ahead of the impeachment vote, which is expected around the middle of the month.

With both sides rallying hundreds of thousands of supporters on to the streets in recent weeks, there are concerns that tensions could lead to violence.

As a possible way out of the crisis, there are growing calls for early elections. Defeated presidential candidate Marina Silva said the electoral court – which is discussing a separate allegation of campaign funding violations – should nullify the 2014 result and allow the public to choose a new leader. But this could take more than a year.

Senators have proposed legal amendments that would allow for early polls, though it is far from clear that this would get the approval of a congress that is deeply fragmented and widely tarnished by the ongoing Lava Jato investigation into corruption at the state-run oil company, Petrobras.

Rousseff told reporters on Tuesday that she would only consider an early presidential election if the lower and upper houses of congress were also dissolved.

“Convince the house and senate to give up their mandates. Then, come talk to me,” the president was reported as saying by the Folha newspaper, which recently ran a front-page editorial calling for the resignations of Rousseff and Temer and new elections.

The head of the senate, Renan Calheiros (who is from the same party as Temer) said he would “look favourably” on the idea of elections this October – two years ahead of schedule.

But any new legislative debates would have to be scheduled by the house speaker, Eduardo Cunha, who is pushing hardest for impeachment and has a great deal to lose if he is voted out of office. Cunha is accused of taking more than $5m in the Petrobras scandal, but his seat in congress gives him immunity from prosecution by lower courts.