"I will take a decision by the end of January", the Germany starlet said.
Since signing for Schalke in 2013, Goretzka has scored a total of 18 goals in 126 appearances in all competitions, while the Royal Blues now sit in third place in the league standings.
The 22-year-old is seen as one of the brightest young talents in world football and has already netted four times for Schalke this season.
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In October , Quebec's Superior Court ruled LaCroix was in contempt of court for continuing to solicit investment into PlexCoins. Lacroix was the target of another order by the Autorité des marchés financiers, Quebec's financial regulator earlier in July.
Having yet to agree an extension to a contract that is due to expire at the end of the 2017-18 season, the highly-rated Germany worldwide has become one of the most sought-after players in Europe over recent months with Liverpool, Manchester City, Real Madrid and Juventus among the other European heavyweights rumoured to be keeping a watchful eye on his situation.
There doesn't exist a deadline, but I think we are in the final phase.
Goretzka is therefore expected to decide his future in January, which coincides with the time when players into their final year of contracts are permitted to speak to other clubs.
Goretzka hasn't confirmed that there is interest from United, or confirmed that he is interested in moving to Old Trafford. According to reports, the Veltins Arena club could offer Goretzka a £10.8 million (€12m) annual contract, which comes down to just over £200,000 a week.