Nairobi , Kenya ( CNN ) Kenyan Deputy President William Ruto on Saturday gave the United Nations ' refugee agency three months to relocate refugees from the Dadaab camp -- the world 's largest -- to Somalia , or `` we shall relocate them ourselves . '' `` The way America changed after 9/11 is the way Kenya will change after Garissa , '' Ruto said in Nyeri , according to a statement from his office . Al-Shabaab gunmen stormed Garissa University College in eastern Kenya this month , killing 147 people . Kenya 's government says that attack was masterminded by senior Al-Shabaab leader Mohamed Mohamud , whose `` extensive terrorist network within Kenya '' extends into the sprawling Dadaab complex , according to a Kenyan government document given to CNN . Students wake to Islamist militants ' terror . Ruto , who is the second highest-ranking person in Kenya 's government behind President Uhuru Kenyatta , said his government has had discussions with United Nations officials about what to do with the camp . On Saturday , a U.N. High Commissioner for Refugees officer said the agency had not received any formal request from Kenya 's government about moving Dadaab . The U.N. refugee agency manages the Dadaab complex , having set up the first camps there in late 1991 amid Somalia 's civil war . The agency and the governments of both Kenya and Somalia agreed in 2013 on a process for the repatriation of Somali refugees . But that was supposed to be mutually agreed-upon and voluntary , in accordance with the refugees ' `` freely expressed wish and their relevant knowledge of the conditions '' where they 'd end up , according to the pact . None of those things , it seems , applies now to the move pushed by Ruto on Saturday . It 's not clear where he expects the refugees to go , other than somewhere into Somalia and out of Kenya . Any mass move would be a monumental task , disrupting the already difficult lives of more than 600,000 Somalis who call the camp their home . Simply meeting basic needs is a challenge in the vast complex , which has seen devastating droughts , contagious diseases and other travails that have tested its residents and those trying to help . Still , as tough as conditions there are , they are seen as a better alternative to life back in Somalia , where Al-Shabaab is based and has carried out violent attacks for years . Yet the Islamist extremist group has n't confined its terror to its homeland , as illustrated by the Garissa attack and the 2013 siege of Nairobi 's upscale Westgate Mall , which ended with at least 67 dead . The Dadaab complex came under government scrutiny after the Westgate Mall attack , too . But just a few weeks later , CNN 's Nima Elbagir managed to go from Somalia to the Dadaab refugee camp undetected by taking one of the panya , or `` rat routes , '' just like many others have done , Al-Shabaab sympathizers among them . Such illicit travel along porous borders as well as police officers ' willful ignorance of migrants ' fake IDs , as acknowledged by then-Interior Minister Ole Lemku , illustrates Kenya 's challenge in keeping out threats from Somalia . That 's why , in addition to moving the Dadaab camp , Kenya is building of a 435-mile ( 700-kilometer ) wall covering most of the Somali border from Mandera to Kiunga -- a wall that Ruto says has begun to prevent Al-Shabaab elements from getting into Kenya . The deputy president also vowed that any businesses collaborating with the militant group will be shut down . These measures are in addition to Kenyan airstrikes on Al-Shabaab camps in Somalia in the days after the Garissa massacre . `` We must secure this country at whatever cost , even if we lose business with Somalia , '' Ruto said Saturday . `` No politics , no games , no half-measures should apply , as the death of the 147 students must touch all Kenyans . '' CNN 's Lillian Leposo reported from Nairobi , and CNN 's Greg Botelho reported and wrote this story from Atlanta .
The Dadaab refugee camp is the world 's largest , with more than 600,000 people . Kenya will change `` the way America changed after 9/11 , '' deputy president says . Garissa adds that `` we must secure this country at whatever cost ''