The Football Association of Wales has arranged a press conference for 2pm where Chris Coleman's successor will be presented to the media.
Giggs' only previous managerial experience came as a caretaker when he took over at Old Trafford for four games during the 2013-14 season following the sacking of David Moyes.
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Coleman spent almost six years as Wales manager before leaving to take over Sky Bet Championship strugglers Sunderland in November.
He never played at a major global tournament as a player and will be hoping to guide Wales to Euro 2020 after they missed out on a place at the 2018 World Cup.
Giggs won 64 caps between 1991 and 2007 but was unpopular with some Wales fans for missing many internationals, especially friendlies.
However, he did spent the following two seasons as Louis van Gaal's right-hand man (which may or may not have worked in his favour).
Wales are in action next at the China Cup in March when they will take part in a four-team tournament with the hosts, the Czech Republic and Uruguay.