The EU will tighten sanctions on the Belarus regime by targeting those closest to its authoritarian leader, the union’s top diplomat has said, as ministers prepare to step up their response to what Brussels terms a “hybrid attack” at its eastern border.

Thousands of people have travelled from the Middle East via Minsk to Belarus’s borders with Poland, Lithuania and Latvia in recent months in the hope of entering the EU. European officials say the surge is being orchestrated by Minsk in retaliation for the bloc’s support for the Belarusian opposition.

Josep Borrell, head of the European External Action Service, the EU’s security and diplomatic arm, said foreign ministers meeting on Monday will give the green light to a widening of the legal framework governing sanctions on Belarus, as part of measures to press authoritarian leader Alexander Lukashenko to stop the flow of migrants to Europe’s borders.