I understand that in British English both are acceptable. If you wish to think of the team as a single unit, then you use the singular `is’. On the other hand, if you think of the team as consisting of distinct individuals, then you use the plural verb `are’. There are many nouns in English which can be followed by either the singular verb or the plural verb: government, family, team, firm, and people. These are just a few.
*The family is/are of the opinion that you should stop teaching. *The Government wants/want to sell off some of the public sector units.