Ukraine’s pro-Western coalition succumbed to bitter personal rivalry last night after the President dissolved parliament and called a snap election.

The move pits President Yushchenko against his former ally Yuliya Tymoshenko in a struggle for political dominance. The feud between the leaders of the 2004 Orange revolution threatens to open the door for their pro-Russian rival Viktor Yanukovych to make a stunning comeback and tilt Ukraine back towards Moscow.

The election will be the third in two years as Ukraine has lurched from one political crisis to another. It threatens to derail the country’s bid for Nato membership at the Nato summit in December and comes as the economy struggles in the face of the global financial crisis.

Mr Yushchenko launched a strong attack on Mrs Tymoshenko, the Prime Minister, in a pre-recorded television address announcing the dissolution of parliament. It was broadcast while he was on a visit to Italy. “I am convinced that the democratic coalition was ruined by one thing alone — the ambition of one person, the hunger for power . . . and the dominance of personal interests over national ones,” he said. The President can dissolve parliament if a new government is not formed within 30 days of the previous one collapsing.

Mr Yushchenko set no date for the election, though many expect it to be held in December. Mrs Tymoshenko is likely to challenge his decision, however, arguing that it is unconstitutional to dissolve parliament before November, a year after deputies were sworn in following the last election. The crisis erupted last month when the parliamentary party supporting Mr Yushchenko quit Mrs Tymoshenko’s ruling coalition, which had only a two-seat majority in the 450-member Rada.

The President’s Our Ukraine party resigned in protest at Mrs Tymoshenko’s support for measures proposed by Mr Yanukovych’s opposition Party of Regions to limit the powers of the presidency. Mr Yushchenko dissolved the parliament last year after accusing Mr Yanukovych, then Prime Minister, of seeking to amend the Constitution to destroy his authority.

In the address Mr Yushchenko accused Mrs Tymoshenko of mounting a “political and constitutional coup d’état” and rejected all attempts to rebuild the coalition. The leader of Our Ukraine in parliament described the alliance with the Party of Regions as a “pro-Kremlin majority”. Mrs Tymoshenko rejected the allegations and accused him of destroying the coalition to damage her chances of succeeding him in presidential elections due next year. Opinion polls consistently rate her Ukraine’s most popular politician, while support for Mr Yushchenko languishes in single figures.

Tensions had already flared between the Orange coalition allies over Russia’s war with Georgia. Aides to President Yushchenko accused Mrs Tymoshenko of “high treason” for failing to condemn the Kremlin’s actions.

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