Mr Clarke said the EU should increase co-operation in areas such as re-uniting migrant families.

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Market observers say the transaction should close before Christmas, re-uniting Telmex and America Movil after Slim spun off the latter in 2001.

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It is not inconceivable that this particular phase of negotiations may hit the buffers, or, perhaps more likely, get bogged down in irreconcilable differences, without that representing the end of all hopes for re-uniting the island.

ECONOMIST: European politics