like the sort of horror waiting, lurching, slowly. everyday we hear that they have reached a little bit more closer to the capital and the people of the capital feel encircled. people of the capital feel encircled. . . ., ~ people of the capital feel encircled. . . w ., ~ encircled. yalda hakim, thank you very much encircled. yalda hakim, thank you very much indeed. encircled. yalda hakim, thank you very much indeed. speaking - encircled. yalda hakim, thank you very much indeed. speaking to - encircled. yalda hakim, thank you very much indeed. speaking to us| very much indeed. speaking to us from lviv. this week we ve heard repeated calls from the ukrainian president for nato to impose a no fly zone over ukraine something the alliance has consistently refused to contemplate. our security correspondent gordon corera explains the reasons why. russian aircraft had been in the skies over ukraine, outnumbering defenders. that s led to calls for what s known as a no fly zone to preven