luxembourg european union ban sale oil oil products north korea monday largely symbolic move aim encourage countries significant level trade country follow suit eu foreign minister also impose blanket ban business north korea sanction go beyond late u.n. measure eu sell oil pyongyang follow north korea powerful nuclear test u.n. security council cap north korean import crude oil china russia resist outright ban eu minister cite persistent threat international peace stability pose pyongyang part measure north korean workers eu estimate 400 mainly poland face low limit amount money send home work visa renew expire sanction add three top north korean officials six businesses blacklist ban travel eu freeze assets take total sanction eu 41 individuals 10 company senior eu official say u.n. sanction target 63 people 53 company institutions eu impose oil embargo north korea symbolic gesture