Latest transfer news: Arsenal sign Merino, Wojciech Szczesny retires while Bournemouth close in on Kepa

Earlier it was announced that Manchester United have reached an agreement in principle to sign Paris St Germain midfielder Manuel Ugarte.

NEW GUNNER: Arsenal unveil new signing Mikel Merino at Sobha Realty Training Centre. Pic: Stuart MacFarlane/Arsenal FC via Getty Images.

Arsenal have completed the signing of Spain midfielder Mikel Merino from Real Sociedad.

An agreement in principle was struck on Thursday night between the clubs for an initial £28.4million transfer with a further £4.2m in add-ons, the PA news agency understands.