According to analysts, BA will report before tax losses of £613m when it publishes its 2009 financial results at the end of this week.
Revenue for the commercial carrier is expected to come in at £7.97bn, while analysts anticipate operating losses to increase to £293m.
The airline said that already it has endured two years of record losses and that reducing costs to ensure long-term survival is a must.
Walsh is faced with further disruptions to the airline’s business this week with the threat of a possible three-week cabin crew strike, the restirring of the Eyjafjallajokull volcano and a new tax on planes.
During the last strike, BA accumulated a loss of £45m when crew walked off the job for seven days.
The current strike threat could disrupt BA’s service during half term, bank holiday and World Cup travel periods.
The news also comes as a new and highly dense volcanic ash cloud forced BA to cancel services to Manchester and Birmingham over the weekend as it continued to drift through the UK’s airspace.
Last month’s six day flight ban hit BA particularly hard as it reported daily losses of up to £20m.
But plans by the Lib-Con coalition to implement a new tax on planes could take the biggest toll on the airline’s business and see BA pay out £150m in taxes a year.
BA criticised the plans and said: “Air travel from the UK is already the most heavily taxed in the world.”
The airline is expected to be the hardest hit from the new tax, which seeks to tax the plane and not the customer, because it flies fewer passengers per plane than budget rivals.