A rail union is calling for an urgent summit to be held on passenger safety as figures showed record numbers travelling on London Underground.
A total of 4.821 million people travelled on the Tube on December 4, making it the network's busiest day ever.
That week was also the busiest in the Tube's history, with 28.76 million journeys. In addition, 18 of the top 20 busiest days ever recorded on the Tube network were in 2015.
Manuel Cortes, general secretary of the Transport Salaried Staffs' Association, said: "We've almost run out of breath this year, repeating our concerns to LU management that cutting the jobs of station staff whilst passenger numbers are rising is dangerous and causing alarming crowding and bottle-necking on platforms and worrying overcrowding on carriages.
"As passenger numbers rise, so have our union's concern for their safety. In the light of these passenger numbers, I call on London Mayor Boris Johnson and Scotland Yard and British Transport Police to meet with heads of rail unions for a summit on passenger security on the Tube as a matter of urgency."
Nick Brown, LU's managing director, said: "The Tube continues to break records for the number of customers we're carrying as London's economy and population keeps on growing. The vast majority of the busiest days in the Tube's 152-year history have been recorded this year.
"The current work to improve London Underground is one of the largest programmes of infrastructure investment in the world. We will continue to invest all our income in modernising the service, improving reliability, train capacity and frequency, and upgrading major stations to provide a Tube network fit for the world city it serves."
Mick Cash, general secretary of the Rail, Maritime and Transport union, said: "The news that Tube passenger numbers have once again broken all records comes against a background of severe and dangerous overcrowding as we try and cram more people into services already busting at the seams.
"To be gearing up to axe over 800 station jobs in just two months' time against this background is a lethal gamble with passenger and staff safety and RMT repeats the call for those cuts to be halted."