UPDATE multiple tables in MySQL using LEFT JOIN

I have two tables, and want to update fields in T1 for all rows in a LEFT JOIN.

For an easy example, update all rows of the following result-set:

SELECT T1.* FROM T1 LEFT JOIN T2 ON T1.id = T2.id WHERE T2.id IS NULL  

The MySQL manual states that:

Multiple-table UPDATE statements can use any type of join allowed in SELECT statements, such as LEFT JOIN.

But I cannot find the proper syntax for doing that in the documented multiple-tables UPDATE.

What is the proper syntax?