Macedonia's Prime Minister Hari Kostov has resigned over disputes within the ruling coalition.
Hari Kostov does did not belong to any of the three governing parties
He said reforms were being neglected and one party's preoccupation with minority rights was getting in the way of economic modernisation.
Mr Kostov, 45, who took office in May, survived a vote of no-confidence in September.
The parliament is expected to meet on Thursday to decide whether to accept his resignation.
Mr Kostov told reporters in Skopje: "I resign as prime minister as there is no will in the coalition for genuine teamwork aimed at crucial goals.
"I am not ready to put up with inefficient work in the government, including putting conditions on and blocking the reform process, in the political sphere and above all in the economic sphere."
He said one of the parties within the coalition government - believed to be the main Albanian party - had been promoting partisan interests, nepotism and corruption.
But Ermira Mehmeti, spokeswoman for the ethnic Albanian party, said the group was "surprised" to hear about the resignation.
"We haven't been informed nor was there any announcement in advance of the resignation," she said.
"We are truly surprised, because we have pointed out many times in the past that co-operation with the prime minister has been good and that problems in the government were solved through discussion and agreement, not clashes."
Mr Kostov's resignation follows a week after an opposition-backed referendum, designed to repeal laws giving minority Albanians in Macedonia greater autonomy, failed after a low turnout.
A former banker, Mr Kostov did not belong to any of the three governing parties.
He was brought into government earlier this year, when the then Prime Minister Branko Crvenkovski became president.
The BBC's Balkans correspondent Nick Hawton says Mr Kostov has felt unable to pursue certain policies, especially in the economic sphere, because of party interests and has had several disputes with ministers.
Macedonia has experienced a period of relative calm since the 2001 conflict, when ethnic Albanian guerrillas fought a six-month campaign to gain more political rights.
The peace deal that ended the violence is still being implemented.