Some 50 world leaders, including Russian President Vladimir Putin and United Nations Secretary-General Ban Ki-moon, will attend the third Nuclear Security Summit (NSS) in the Hague on 24 and 25 March, Dutch media Tuesday reported. The Hague's mayor, Jozias van Aartsen, said very strict security measures will be imposed and traffic in and road around The Hague will also be severely disrupted during the two-day meeting.The Kurhaus hotel where a number of international leaders will be staying will be surrounded by a security fence.Van Aartsen said he has no choice but to ensure very strict security."We are used to our ministers and mayors cycling and luckily that is still possible. But we have to do what is asked of us. Otherwise people will not come to the Netherlands and this summit is very beneficial to us," he was quoted saying.The first NSS was held in Washington in 2010 and the second summit was held in Seoul in 2012.