As per the updated news sitemap specs, the publication language tag's value in the news sitemaps should be 2 or 3 characters and should be picked from the ISO 639-2 list.

The fact the publishers has to pick their publications' language from this list doesn't mean that Google News supports all of these languages. Picking a language which isn't in one of the Google News editions may prevent Google to include the articles in Google News.

At the moment the following languages are fully supported:

• English,
• German,
• French,
• Spanish,
• Italian,
• Polish,
• Portuguese,
• Chinese,
• Japanese,
• Korean,
• Dutch,
• Arabic,
• Hebrew,
• Norwegian,
• Czech,
• Hungarian,
• Swedish,
• Greek,
• Russian,
• Hindi,
• Telugu,
• Tamil,
• Turkish
• and Malayalam.