BRASILIA: Brazilian President Dilma Rousseff was left scrambling for votes to save her presidency in a looming impeachment showdown after her main coalition partner walked out of the government Tuesday.

The PMDB, the country’s largest party, voted to immediately end its alliance with Rousseff’s leftist Workers’ Party, or PT, and go into opposition.

“From today, at this historic meeting of the PMDB, the PMDB withdraws from the government of President Rousseff,” said Senator Romero Juca, the party vice president.

According to a poll on Wednesday, Rousseff’s popularity remains close to historic lows, amid a mounting political crisis following the loss of her main coalition partner this week that increased the risk of her impeachment.

Pollster Ibope said the number of Brazilians who consider Rousseff’s government “great” or “good” edged up to 10 percent from a record low of 9 percent in the previous survey in December.

The meeting, broadcast live on national television, was the culmination of a long divorce with Rousseff, leaving Brazil’s first female president grasping at straws as she tries to stay in power.

The vote and announcement took no more than three minutes and was accompanied by singing of the national anthem and shouts of “PT out!”

The split plunges Rousseff’s government into fresh crisis mode and, more seriously, greatly reduces her chances of mustering the one third of votes in the lower house of Congress that she needs to defeat a first impeachment vote, expected in April.

“If you look at the numbers, that’s basically it,” said Everaldo Moraes, a political science professor at Brasilia National University.

Rousseff canceled a trip to Washington for a nuclear safety summit on Thursday and Friday, the state news agency said. A government spokesman said that in “the current political context,” it was not advisable.