join forces
US /dʒɔɪn ˈfɔːrsɪz/
UK /dʒɔɪn ˈfɔːrsɪz/
1.
to combine efforts or resources with another person or group to achieve a common goal
:
•
The two companies decided to join forces to develop a new product.
•
We need to join forces if we want to win this competition.