A Moldovan court on Sunday forced out President Igor Dodon, deepening a standoff between rival political parties over the formation of a new government after months of deadlock.
Former Prime Minister Pavel Filip was appointed to replace Mr. Dodon, and he promptly announced snap elections in September.
Mr. Filip said that Mr. Dodon had not fulfilled his duties by failing to dissolve Parliament and had attempted to stage a “coup.”
The crisis threatens more instability in the former Soviet republic, one of Europe’s poorest nations, which has a population of 3.5 million. Entrenched corruption and low living standards have pushed many citizens to emigrate to Russia or to other European countries.
On Saturday, Mr. Dodon’s Russian-backed Socialist Party announced that it was forming a coalition government with a rival bloc, A.C.U.M., which favors greater cooperation with the European Union. That unlikely alliance was intended to keep the Democratic Party of Moldova, run by the tycoon Vladimir Plahotniuc, out of power.
The Democratic Party, to which Mr. Filip also belongs, said that the new administration had tried to usurp power at Russia’s behest and criticized Mr. Dodon’s refusal to dissolve Parliament after the parties missed a court-mandated June 7 deadline to form a government.
Thousands of supporters of the Democratic Party rallied in the capital, Chisinau.
Denouncing the decision to remove him from the presidency, Mr. Dodon said the court was not politically independent and accused the Democratic Party of trying to cling to power. He called on the international community to step in.
“Moldovan citizens with different views on domestic and foreign policy can unite for the sake of a common goal: liberation of the Republic of Moldova from the criminal, dictatorial regime,” Mr. Dodon said in a statement.
“In this situation, we have no choice but to appeal to the international community to mediate in the process of a peaceful transfer of power,” he added, urging Moldovans to take part in “an unprecedented mobilization and peaceful protests.”
As signs of trouble brewed in Moldova on Saturday, a spokeswoman for the European Union called for “calm and restraint” and for the country’s leaders to respect the rule of law and democracy. Russia urged all parties to avoid destabilization.
Maia Sandu, the leader of A.C.U.M., who is a former education minister and World Bank adviser, was appointed prime minister on Saturday. But a court struck down her appointment and that of a speaker of Parliament also nominated by the Socialist Party.
Supporters of the Democratic Party pitched tents in front of several ministries and state institutions on Saturday night.
Ms. Sandu said in Parliament on Sunday that the pitched tents “are proof that the Democratic Party wants to use law enforcement bodies to throw the country into chaos to protect a single person: Plahotniuc.”
“They do not want to ensure the peaceful transition of power,” she added.
Moldova has been dogged by political instability and graft, including a breathtaking scandal in 2014-15, in which $1 billion, around an eighth of the country’s economic output, was pilfered from three banks.
Moldova, lying between Ukraine and Romania, is politically divided, with some favoring closer ties with the European Union or even reunification with Romania, which is a member of the bloc, and others preferring tighter links with Russia.
The European Union forged a deal on closer trade and political ties with Moldova in 2014 and showered the country with aid, but the bloc has become increasingly critical of reform efforts. An election in February produced a hung Parliament, setting the stage for months of coalition negotiations.
On Saturday, Andrian Candu, deputy chief of the Democratic Party, said that Mr. Dodon had approached the Democrats with a coalition offer on terms set by Moscow. The terms included a longstanding plan to turn Moldova into a federal state that would give special recognition to the separatist region of Transdniestria, where many want to merge with Russia.
Opponents of such a plan say it would give Transdniestria, and by extension Russia, an outsize role in how Moldova is run.
Mr. Dodon has said that the idea to federalize Moldova came from Mr. Plahotniuc, who had offered the move to Moscow in exchange for dropping criminal cases against him in Russia. A Russian statement also said that the idea had come from Mr. Plahotniuc.