Felix Tshisekedi is facing his maiden test as president of Democratic Republic of Congo - not from rivals in the political arena, as many have expected, but from striking workers.Since the December 30 elections, labour unrest in the public sector has exploded as unions, eyeing a new regime headed by a former opposition leader, demand back payment of wages and a crackdown on cronyism.Stoppages have hit transport, a key port, television, insurance and the fire service and were continuing on Wednesday as Tshisekedi was in Kenya on his first foreign tour.Although the public sector is only a small part of the national economy - most Congolese work in small- or medium-sized private businesses - the strikes are providing an early trial of Tshisekedi's political smarts."Baptism of fire," the daily Le Potential said, wondering whether Tshisekedi had the power to match his electoral rhetoric with deeds.Head of the Union for Democracy and Social Progress (UDPS), the country's oldest and largest opposition party, Tshisekedi vowed on the campaign trail to combat poverty and root out graft.After a ballot marked by repeated delays and a bitterly-disputed result, he succeeded President Laurent Kabila, whose 18-year tenure was marked by authoritarian rule, patronage and crackdowns.It was the first peaceful transition in the history of the Democratic Republic of Congo (DRC) - a state that traces its origins back to independence from Belgium in 1960. Multiple strikes Tshisekedi had to weigh into a dispute on January 28, just three days after his inauguration.He ordered "urgent" payment of backdated wages to workers at the Congo Transport Company (Transco), which runs the bus services for the sprawling capital, Kinshasa.The government also suspended Transco's boss for "poor management".But on Monday, Kinshasa firefighters went on strike, saying they were owed 38 months' salary and urging Tshisekedi's new government to put pressure on city governor Andre Kimbuta.The same day, dozens of workers on temporary contracts at RTNC demonstrated outside Tshisekedi's temporary residence, demanding job security and the firing of their boss, Ernest Kabila, for alleged cronyism.At the Atlantic port of Matadi, workers began a strike on February 1 to demand back-payment of four months' wages and the ousting of their boss, "who is suspected of having siphoned off $30m", said Mazime Nzinga, head of the DRC Custom Officers Association. The boss, Mukoko Samba, denied the accusations.In Boma, in the same region, maritime transport workers are also on strike, demanding 20 months' back pay, and state firms involved in telecoms and insurance have also been hit by unrest.Tshisekedi faces familiar problems of budget constraints when seeking to defuse these problems, as well as a daunting political tightrope act.Pushing out Kabila-era appointees could endanger the delicate sharing of power that he has had to forge with supporters of his predecessor, who wield a huge majority in parliament.But he also has to ensure presidential credibility in the light of the disputed election result.Another opposition candidate, Martin Fayulu, contends the result was cooked up between Kabila and Tshisekedi, denying him a victory after he says he won 61% of the vote."I know that there have been some imperfections, some irregularities in these elections, but overall it went well because this change of leadership was done peacefully," Tshisekedi said on Tuesday.Sign up to News24's top Africa news in your inbox: SUBSCRIBE TO THE HELLO AFRICA NEWSLETTERFOLLOW News24 Africa on Twitter and Facebook.