U.S. Secretary of State John Kerry, during a trip to London, issued a warning to Iran and Syria, telling them they must embrace change, UPI reported. "[The] Syrian people deserve better than the horrific violence that now invades and threatens their everyday lives -- the lives of innocent people, the lives of people who simply want an ability to have their government be accountable and to be able to be part of the governance of their own live," Kerry said during a news conference with British Foreign Secretary William Hague after a meeting. Kerry said he and Hague condemned the "indiscriminate killing of innocent civilians" by Bashar Assad's regime. "And it is just further evidence that Assad has to go," he said. Kerry thanked Hague for the British effort to "help dial up the pressure on the regime, for their contributions of humanitarian aid, and for hosting the transition conference last month." Hague said he and Kerry would attend the Rome meeting of the Friends of Syria this week. "An appalling injustice is being done to the people of Syria, which the world cannot ignore," Hague said. Concerning Iran, Kerry said Iran having a nuclear weapon is "simply unacceptable." "And as we've repeatedly made clear, the window for a diplomatic solution simply cannot by definition remain open forever," he said. "But it is open today. It is open now. And there is still time, but there is only time if Iran makes the decision to come to the table and to negotiate in good faith." London is Kerry's first stop on his first foreign trip as U.S. secretary of state. He is set to meet with other leaders in Germany, France, Italy, Turkey, Egypt, Saudi Arabia, the United Arab Emirates and Qatar.