A British warship arrived in Japan’s Yokosuka port on Wednesday with the aim of joining international efforts to enforce sanctions on Pyongyang by monitoring any prohibited trading by North Korea at sea. Royal Navy Capt. Paul Casson said the frigate HMS Southerland will join exercises with Japan’s navy and monitor attempts by North Korea to evade UN-imposed sanctions, AP reports. The UK said it will send two more warships to Japan later this year to participate in the monitoring operation and join exercises in the region. The UN has toughened its sanctions on North Korea over its nuclear weapons development.