LONDON, July 2 (Reuters) - The median pay of chief executives at Britain"s top companies fell for the fourth straight year to 2.85 million pounds ($3.92 million) in 2020, consultants Deloitte said on Friday. The drop, from 3.3 million pounds in 2019, came as many bosses took pay and bonus cuts in response to the hit to revenues caused by the COVID-19 pandemic, and after pressure from investors to rein in remuneration. Around a third received no bonus in 2020, up from 6% in 2019, while more than half of the CEOs, 55%, will also face a salary freeze for 2021, Deloitte said. Following investor pressure, more than 95% of companies had agreed to cut existing executive pensions, with most pledging to align them with the wider workforce by the end of 2022. Despite that, the number of companies to face a material rebellion on pay at their annual meeting - considered anything less than 80% support - more than doubled to 12% in 2021, from 5% in the prior year. "Shareholders were clear at the outset of the pandemic that decisions on executive pay should reflect the wider workforce, investor and societal impact of the COVID-19 pandemic," said Deloitte Vice Chair Stephen Cahill. "While the vast majority have shown restraint, investors remain focussed on pay fairness and will vote against remuneration reports where executives are seen to be insulated from the wider stakeholder impact." ($1 = 0.7272 pounds)