Swedish centre-right gets first try at forming government, but chances slim (Update 1)

Sweden's parliamentary speaker on Tuesday gave a centre-right bloc of parties two weeks to form a government, granting its leader a broad mandate that he may struggle to fulfil following inconclusive national elections.

The opposition four-party Alliance won 143 seats in the 349-seat legislative chamber in the Sept. 9 ballot, one fewer than the centre-left bloc headed by the Social Democrats.

Both blocs face a daunting task to form a government, having ruled out cooperating in government with each other or with the anti-immigration Sweden Democrats, which hold the balance of power with 62 seats.

"The parties have to rethink their positions in order for a government to be formed," Speaker Andreas Norlen said. "I am the speaker, not a magician."

Norlen said Alliance leader Ulf Kristersson had on balance a stronger case to govern than caretaker Prime Minister and Social Democrat leader Stefan Lofven.

Kristersson had two weeks to report on whether he had been successful, Norlen told reporters after meeting all party leaders during the day.

Kristersson was not limited to forming a government with just his four Alliance allies, of which his Moderates are the biggest party.

In Sweden, a prime minister can assume office as long as a majority in parliament does not vote against him or her.

The Sweden Democrats have said they will vote against any government that does not give them influence over policy while Lofven has ruled out supporting an Alliance government.