Moldova plunged deeper into crisis Sunday as a new, acting president dissolved parliament and called elections just after lawmakers appeared to have formed a government following months of wrangling.

One of Europe's poorest nations, the ex-Soviet state has been in political chaos since a general election in February failed to give a clear majority to any party.

On Saturday, parliament approved a new government based on an unprecedented alliance between pro-Russian and pro-European forces.

The Socialist Party of then-president Igor Dodon agreed to work with the pro-European ACUM alliance and freeze out the previously ruling Democratic Party, led by the powerful oligarch Vlad Plahotniuc.

The parties said the state was being held ‘captive’ by oligarchs, adding that the country was ‘wallowing in corruption’.

However the coalition was formed after the Constitutional Court ruled Friday that fresh elections should be held.

On Sunday, the court suspended president Dodon and appointed Pavel Filip, the former prime minister from the Democratic Party, as interim leader.

Filip said Dodon had been suspended because he had refused to sign off on parliament's dissolution.

The new acting president immediately called a snap vote for September 6.

The European Union urged ‘calm and restraint’ and said in a statement it was ‘ready to work with the democratically legitimate government’.

EU foreign policy chief Federica Mogherini called on Moldova to ‘respect the rule of law and guarantee democracy’.

Neighbouring Romania's President Klaus Iohannis separately called for ‘responsible dialogue of all political forces.’

- 'Desperate step' usurps power -

Thousands of supporters of the Democratic Party held a rally in the centre of the capital Chisinau on Sunday, attended by Filip.

The party bussed in large numbers of people amid a heavy police presence.

In a speech, oligarch Plahotniuc said: ‘We will go to the elections set for September 6 and win the trust of the public.’

He said Dodon was ‘not worthy of occupying the post of president.’

Filip said the Democratic party had not wanted snap elections but ‘in the current parliament, there is no one to work with.’

Dodon meanwhile said he was also considering the option of calling on Moldovans to take part in ‘peaceful protests’.

He called his suspension a ‘desperate step’ and an attempt to ‘usurp power’.

The suspended president complained Sunday that the Democratic Party did not want to ‘peacefully hand over power to a lawful parliamentary majority and a lawful government.’

‘We have no choice but to appeal to the international community with a call for it to act as a moderator in the process of peaceful handover of power,’ Dodon said.

The Constitutional Court has already suspended Dodon several times in the last two years when he refused to back laws or appoint ministers.

Moldova, once part of Romania and later a Soviet Republic, contains a Russian-backed breakaway region called Transnistria.

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