Global business

A former trader went on trial in London over the LIBOR scandal. Tom Hayes, whose former employers included UBS and Citigroup, was described by prosecuting lawyers as the alleged "ringmaster" of efforts to manipulate the benchmark interbank interest rate. He pleaded not guilty to eight charges of conspiracy to defraud. It is the first time someone has appeared in the dock on LIBOR charges, though a few bankers have pleaded guilty in related cases rather than face a court.

The IMF declared that China's currency is no longer undervalued because of its "substantial real effective appreciation over the past year." This puts the IMF at odds with the United States, which reckons the Chinese government keeps the yuan at an artificially low rate in order to gain a trade advantage. In March, Jacob Lew, U.S. Treasury secretary, read out a long list of concerns about the slow pace of reforms to China's economy, and included the management of the exchange rate among them.

The share price of Broadcom, a chipmaker, surged by more than 20 percent amid reports that it was the target of a bid by Avago Technologies, in what could be the biggest takeover in the semiconductor industry to date.

The Irish government gave its approval to the proposed takeover of Aer Lingus, Ireland's national airline, by IAG, which owns British Airways. IAG still needs the support of Ryanair, which holds a 30 percent stake in Aer Lingus, for its bid to succeed. Ryanair, meanwhile, said its profit had surged by 66 percent in the 12 months ended March 31, to €867 million ($1.1 billion).

Uber was handed another setback, this time in Italy, where a court in Milan banned its app-based unlicensed car-sharing service across the entire country. Licensed taxi drivers argued that Uber creates unfair competition, a gripe that has been echoed in the many legal cases brought against Uber around the world. It has two weeks to comply with the Italian ruling.

The growth of the global market for smartphones will slow this year to 11.3 percent, according to IDC, a market-research firm. That is down from 27.6 percent last year and a bit lower than IDC's previous forecast. The main reason is that the Chinese market is nearing saturation point and is predicted to rise by just 2.5 percent in 2015.

Evan Spiegel, Snapchat founder

Evan Spiegel, 24, founder of Snapchat, a photo-messaging app that was valued at $15 billion after a round of fundraising in March, confirmed that his firm is preparing for an IPO, though he didn't say when.

Political economy

Andrzej Duda of the conservative Law and Justice (PiS) party defeated the incumbent, Bronislaw Komorowski, of the centrist Civic Platform party, in an upset victory in Poland's presidential election. The PiS is also ahead in the polls for the general election due in the autumn.

Spain's regional elections saw large gains for two upstart parties, the left-wing Podemos movement and the liberals of Ciudadanos. However, fragmented left-wing parties will face difficult negotiations to form coalition governments in most of Spain's regions.

Denmark's prime minister, Helle Thorning-Schmidt, called a general election for June 18. Her center-left coalition has been in office since 2011, but an anti-immigrant party is polling well.

David Cameron outlined his new government's agenda in Queen Elizabeth's speech to Parliament, the first from a conservative majority government since 1996. As promised, a referendum on Britain remaining in the E.U. was included. Cameron met Jean-Claude Juncker, the president of the European Commission, last week to set out his plan for renegotiating Britain's membership.

The FARC, a leftist guerrilla army that has been fighting Colombia's government for 50 years, suspended a cease-fire it had declared in December. The war has escalated in recent weeks. Colombia's president, Juan Manuel Santos, ordered the resumption of air raids after the FARC killed 11 soldiers in April; 27 FARC guerrillas were then killed by Colombian attacks. Despite the fighting, both sides resumed peace talks in Havana.

Leopoldo López, an imprisoned leader of Venezuela's opposition, started a hunger strike. He is demanding that the regime led by Nicolas Maduro free political prisoners, end censorship and hold elections.