The Dutch foreign office is recommending that people travelling to Belgium avoid crowded places and the metro in Brussels, broadcaster Nos said at the weekend.

The warning follows a major security alert in the Belgian capital and warnings of an imminent terrorist attack.

‘We are not saying people should avoid Belgium, but in terms of Brussels, we are advising them not to use the metro or attend mass events,’ foreign minister Bert Koenders told NPO radio on Saturday. ‘You have to keep your wits about you.’

Meanwhile, German media are reporting that last Tuesday’s friendly football match between the Netherlands and Germany was cancelled after French spies warned that Hanover’s stadium was being targeted with a ‘five bomb plot’.