Sanctions against Belarus for the “hijacking” of a passenger plane carrying a journalist who had been critical of the Lukashenko regime must be “fully implemented,” the head of NATO has said. Secretary-general Jens Stoltenberg met Prime Minister Boris Johnson in Downing Street on Wednesday and the pair discussed the future of the alliance ahead of a leaders’ meeting in Brussels on June 14. Speaking to journalists afterwards, Johnson suggested “standing together against threats from the east” is likely to feature heavily on the agenda for the summit, as the NATO chief said the Belarus incident had ties with the “assertive” behaviour of Russia. Stoltenberg said the arrest of journalist Roman Protasevich was “absolutely unacceptable” and added that NATO has called for him and his girlfriend to be released as well as for an “impartial international investigation” to be carried out. He said: “I welcome sanctions imposed by the United Kingdom …