Arsenal and Chelsea have sold only around half of their tickets for the Europa League final in Baku.

The London rivals may take just 3,000 fans each to Azerbaijan, with half of their 6,000 allocations set to be returned unsold. The cost and difficulty involved in making the 5,500-mile round-trip has put large numbers off travelling.

European football's governing body UEFA were forced to apologise on Friday for the problems supporters are having trying to get to Baku following a strongly worded letter of complaint by Arsenal.

Arsenal and Chelsea have only sold half of their allocations for the Europa League final in Baku

And those difficulties will be underlined during the showpiece on Wednesday week by the lack of fans from the two Premier League clubs in their respective sections of the 68,700-capacity stadium.

Baku Airport can only accommodate 15,000 visitors a day and most fans have to take flights with changes in Turkey, Germany, Ukraine or the Middle East to reach there.

The journey is so awkward some have had to take up to a week off work for a trip that, all-in, could stretch to as long as eight days. Arsenal issued a statement on Thursday demanding answers about the ticketing and travel chaos overshadowing the final.

The journey from London to Baku is so arduous some fans have taken a week off from work

UEFA's competitions director Giorgio Marchetti said in response: 'An all-English final played by two London teams was not a very predictable event at the time of the appointment.

'This has added significant difficulties to the event logistics. We are really sorry for the problems that your (and Chelsea's) fans are encountering trying to organise their journey to Baku.

'Our experts are keenly working on this matter with a view to help find cheaper solutions for travelling fans. We would welcome a joint effort with your club in this respect.'

Both clubs have already enlisted the help of Thomas Cook to come up with a £979-per-person day-trip to Baku to reduce costs. Arsenal said the situation was 'unacceptable and cannot be repeated' but Marchetti defended UEFA's decision to pick Baku as the host venue.

He said: 'It is fair and due not only to give other fans the possibility of a unique live experience, but also to stage events which can boost the promotion of football in an entire region. That's why UEFA would consider it unfair to exclude venues based on their decentralised geographical position.'

Arsenal sought answers over the decision to play in Baku and said events 'cannot be repeated'

It is understood that UEFA are perplexed by criticism of Baku and its airport and feel that it is the responsibility of the clubs to partner with tour agents and ensure that enough flights are chartered for fans.

Azerbaijan FA general secretary Elkhan Mammadov claimed that Baku Airport was built to handle 10,000 visitors per hour and said: 'Flights to Baku from the UK are still available via Istanbul, Frankfurt, Tbilisi and Moscow with an average economy price of £394.'

Mammadov revealed that, as of Friday, more than 25,000 tickets had been sold internationally and another 10,000 in Baku since going on sale four days ago.