MILAN, March 20 (Reuters) - Telecom Italia shareholder Merlyn Partners proposed on Wednesday that the company sell its Brazilian unit this year as part of a radical restructuring of the debt-laden Italian former phone monopoly.

The Luxembourg-based alternative investment fund, which held 0.53% of Telecom Italia (TIM) as of Tuesday, also suggested TIM should sell off its consumer business with a target closing a deal in 2025.

Having previously challenged the plan, Merlyn now said that TIM should seek to conclude the sale of its landline grid to KKR in a 22 billion euro ($23.9 billion) deal "as soon as possible" and hopefully by this summer.

The sale of the network grid is the centre-piece of TIM CEO Pietro Labriola's efforts to reshape the debt-laden group but TIM shares plunged this month when he set out financial targets for the new TIM.

Merlyn's break-up plans are more ambitious and would leave what it called "TechCo", a tech and infrastructure company serving business and public administration.

($1 = 0.9224 euros) (Reporting by Elvira Pollina; writing by Gianluca Semeraro and Keith Weir; editing by Mark Potter)