The Immigration Minister Damian Green has blamed the rain for the length of queues at Heathrow airport, saying: "This was caused mainly by the severe weather leading to flight diversions and changing flight schedules and the bunching of arrivals."
The lengthy queues have been criticised by the shadow immigration minister Chris Bryant, London Mayor Boris Johnson and airlines.
More top news
Mladic, now 75, was the military commander of Bosnian Serb forces in the 1990s, who fought against the Bosnian Croat and Bosniak armies.
Weather: Heavy rain and strong winds in the north
His representatives said Cassidy, who was hospitalised last week, died "surrounded by those he loved."