Unions want to see no compulsory redundancies after any takeover

Talks for the union side are being coordinated by UNI Finance, part of the UNI global union that represents three million finance workers worldwide.

The invitation to talks came from Barclays' chief executive John Varley.

Unions are concerned at the impact of any takeover on jobs, with the Barclays-ABN Amro link-up envisaged to affect more than 23,000 positions.

During the talks, the unions will be pressing Barclays for no compulsory redundancies, preserving collective agreements and working conditions, and seeking a new European Works Council for a merged bank.

They will also be seeking "a global agreement between the bank and UNI Finance to ensure union rights around the world, group-wide dialogue on integration if the merger goes ahead, and effective information and consultation".

In April, Barclays agreed to merge with ABN Amro in a deal worth �45bn (66bn euros; $90bn).

The move would create one of the world's biggest banks, valued at �94bn, with its headquarters in the Netherlands.

The companies said about 12,800 jobs would be cut as a result of any merger, with a further 10,800 jobs moved to low-cost locations.