US Secretary of State John Kerry urged Syria's opposition on Monday to attend a planned international meeting in Rome this week, saying that US President Barack Obama was evaluating further steps required in order to help protect Syrian civilians. Kerry also addressed the upcoming negotiations in Kazakhstan on Iran's nuclear energy program set to begin on Tuesday, stating that the United States is still willing to pursue diplomatic routes, but not for long."Today we were discussing various options and I'm not going to go into what they may or not be at this point in time," he told reporters on a visit to London where he met British officials."I want our friends in the Syrian opposition council to know we are not coming to Rome simply to talk. We're coming to Rome to make the decision about next steps and perhaps even other options that may or not be discussed further after that." The Syrian opposition is boycotting the meeting in Rome due to the leading rebels belief that the meeting will not result in the provision of the material and weapons support they need to overcome President Bashar Assad's forces. In his statements, Kerry also addressed the upcoming talks with Iran set to take place in Kazakhstan with the P5+1 attending. Kerry expressed that Iran still has time to find a diplomatic solution to the international standoff over its nuclear program but the Islamic Republic must negotiate with world powers in good faith."The window for a diplomatic solution simply cannot by definition remain open forever. But it is open today. It is open now," Kerry told reporters in London."There is still time but there is only time if Iran makes the decision to come to the table and negotiate in good faith. We are prepared to negotiate in good faith, in mutual respect in an effort to avoid whatever terrible consequences could follow failure. And so the choice really is in the hands of the Iranians. And we hope they will make the right choice."