Phil Cain in Graz, Austria -

The maturity of Kosovo's political system faces a stern test after February's appointment of a controversial construction tycoon as president was ruled unconstitutional, leaving the government scrambling to find a way to avoid fresh elections.

Kosovo's Constitutional Court said on March 28 that the election of Pacolli as president was illegitimate, because there was no candidate standing against him and fewer than two-thirds of the 120 MPs took part in the session that attempted to vote him into office. Only 67 MPs took part in the February 22 session, 62 giving Pacolli their support in the third round.

Seven of the nine constitutional court judges approved the decision to invalidate Pacolli's tenure. Those presiding included three foreigners, two representatives of Kosovo's ethnic minorities, and two members appointed by the ruling majority and two by the opposition. The Portuguese and US judges voted in favour of fresh elections, but their colleagues were unconvinced.

Fresh elections?

Prime Minister Hashim Thaci may have no choice now but to call new elections unless he finds a way out of an increasingly dense presidential thicket. Thaci has good reason to fear a return to the ballot box with his Democratic party seeing its share of the vote slide in a snap parliamentary election in December. The biggest winner of any new election looks likely to be the Self-Determination party. Its 36-year-old leader Albin Kurti's star is rising among younger voters for railing against the international community and the Kosovo Serb minority. The Self-Determination party picked up 12% of the vote in December's poll.

There is little time for Thaci to resolve the crisis without an election, with the administration already paralysed. Since March 30, no legislation can be signed off until a legitimate president is appointed (among the items of legislation awaiting the presidential rubber stamp is the recently-passed 2011 budget). An interim president is no longer possible because parliamentary speaker Jakup Krasniqi has held the position for the maximum period of six months since it fell vacant on September 27 when Fatmir Sejdiu abruptly resigned, so triggering December's elections. The 35 days that Pacolli was called president also count as part of the interim period because his title has been found to have no legal standing.

Pacolli's departure also poses an existential challenge to the government coalition of Thaci, which took from December until February to form. Pacolli's installation as president was key to bringing his supporters' on board. Thaci has now to try to find a way to prevent the coalition agreement from dissolving while, at the same time, gaining the approval of the opposition. The opposition might otherwise simply boycott the parliamentary session called to appoint a president, so again invalidate the outcome.

Pacolli hasn't ruled out running a second time. However, his chances of making it back are slim. Rumoured to be the world's richest Albanian, he is the president and chief executive of the Mabetex Group, a Swiss-based construction company that landed a series of lucrative contracts with Russia's administration under Boris Yeltsin in the 1990s. These business links to Russia, staunchly supportive of Serbia's opposition to Kosovo's independence, are the source of implacable dislike and distrust among some fellow countrymen.

Yet if Pacolli does not run for the presidency again, "There is no way out for the government coalition, because Pacolli will want something in exchange for losing his position as president," says Martin Prochazka, an analyst. It may be, however, that Pacolli is amenable to rewards other than gaining high office.

In any case, Thaci must at least be considering an alternative to Pacolli who the opposition parties - the Democratic League, the Alliance for the Future and Kurti's Self-Determination party - can live with.

There are few names to play with. The strongest candidate among them may be former prime minister Agim Ceku, a career soldier and widely-respected former commander of the Kosovo Liberation Army, which fought a guerrilla war to gain independence. But his candidacy might still require the Thaci government to offer further concessions to the opposition.

Another potential compromise-candidate might be 75-year-old Adem Demaci, who spent 28 years in prison for speaking out for the rights of Kosovo Albanians. Some would see him as a Nelson Mandela-like figure, although few think he comes close in terms of political skill or personal charm.