However, so far, the transfer has not been concluded and Moyes opted not to offer any specific updates when he met the media for the first time on Friday.
Reports have emerged in Spain, though, that representatives of both clubs will meet next week to finalise the transfer.
Thiago is available at a cut-price £17million as he did not feature in the number of first-team games stated in his Barca contract and it is claimed will sign a five-year deal to become Moyes' first significant capture since replacing Sir Alex Ferguson.
"Manchester United will always be close to the best players," Moyes told MUTV.
"I will inform the supporters as much as I can.
"Some things are confidential but I am doing everything I possibly can to strengthen the current English champions."
The deal could be rushed through in time to make Thiago available for the start of United's pre-season tour on Wednesday.
However, given the highly-rated player's successful run to the European Under-21 Championship final with eventual winners Spain, he may not be called up for the first part of the three week expedition to the Far East and Australia anyway.