LONDON — The British Parliament on Wednesday authorized airstrikes in Syria against the Islamic State, in a vote that became a wider test of British willingness to play an active role in international affairs, and British warplanes made their first attacks hours later.

Early on Thursday, the Defense Ministry said that four Tornado jets took off from the Akrotiri Royal Air Force Base in Cyprus and returned to base safely after carrying out airstrikes, according to British news reports. The ministry did not provide specific details of the airstrikes.

The vote, after months of wrangling, hand-wringing and a daylong parliamentary debate, underscored the concerted efforts of Prime Minister David Cameron, whose Conservative Party has a majority in Parliament, to restore Britain’s reputation as a serious global actor.

“The threat is very real,” Mr. Cameron said of the Islamic State, also known as ISIS or ISIL, on Wednesday, as he opened the debate in the House of Commons. “The question is this: Do we work with our allies to degrade and destroy this threat?”