LONDON, March 7 (Reuters) – British Airways hopes to sign its merger agreement with Spanish airline Iberia by the end of this month, and said a potential strike by its cabin crew had not impacted forward bookings.

''We're aiming to sign the merger agreement with Iberia by the end of the first quarter of 2010, that's the plan,'' BA's group treasurer George Stinnes told reporters on a conference call.

BA faces a costly strike after its cabin crew last month gave overwhelming backing for industrial action.

Chief Executive Willie Walsh, however, told a meeting of the airline's staff on Wednesday that as many as 6,000 workers had volunteered to support the airline in the event of a strike, by undertaking additional duties.

A spokesman said 1,000 of the volunteers would be fully trained to work as cabin crew.

The airline has about 13,500 cabin crew, mostly based at Heathrow and Gatwick airports in London.

The Unite union has not yet set a date for the walkout, but Stinnes said the uncertainty had not hit BA's bookings for March.

''It (the potential strike) has made no real difference to March bookings ... bookings for March are strong and show a steady improvement year-on-year,'' he said.

BA said it carried 1.1 percent more passengers in February year-on-year, boosting hopes that air traffic demand is recovering.

The airline said the number of its premium, or business class, passengers continued to rise, jumping 5 percent on the 2009 figure, while non-premium traffic edged up 0.3 percent on the same month last year.