Ryanair has reported record annual profits of €1.9bn (£1.6bn) as the Irish airline announced the appointment of former UK home secretary Amber Rudd to its board and said summer fares would be lower than previously expected.

Profits after tax increased by more than a third in the year to the end of March compared with the previous year as the number of passengers increased by 9% to 184 million – 23% above the heights reached before the pandemic.

The Dublin-listed company said it expected to carry as many as 200million passengers in the current financial year, but added that the prices it could charge were lower than expected in recent weeks.

Ryanair said it expected prices to be “flat to modestly ahead of last summer”, but that “recent pricing is softer than we expected”, pushing it to offer lower fares to attract customers.

Rudd was energy and climate change secretary under David Cameron and then home secretary for nearly two years under Theresa May, before resigning in 2018 in relation to the scandal over the mistreatment of the Windrush generation of migrants to the UK. She did not seek re-election in 2019.

Rudd, who was an investment banker before becoming an MP, has since worked for public relations companies, as an adviser to Darktrace, a cyber-security company that is being bought by a US private equity investor, and on the board of the British Gas owner, Centrica. She joins Ryanair as a non-executive director on 1 July.

Ryanair’s ever-increasing passenger numbers have made it the world’s second-largest airline by market value, but also one of the EU’s biggest polluters.

The airline argues that its purchase of new aircraft will help it to improve its fuel efficiency. That could reduce carbon emissions for each passenger, although the total emissions of the airline industry are expected to increase roughly in line with passenger numbers.

Ryanair’s efforts to increase passenger numbers, and to cut its fuel use for each passenger, have been hampered in recent years by the travails of the US plane manufacturer Boeing. The airline said it expected to take delivery of 12 new Boeing 737 Max aircraft between March and July, but said it would be 23 short of the contract with the manufacturer after repeated scandals over safety that have caused delays in deliveries.

Michael O’Leary, the Ryanair chief executive, said: “We plan to deliver as much growth as possible for passengers and airport partners in [summer 2024], although these delays mean more traffic growth will occur in lower yielding [second half] than planned.”