Curaleaf Holdings said Tuesday it signed a $286 million definitive agreement to acquire London-based medical marijuana company Emmac Life Sciences, giving the Massachusetts-based multistate operator a major foothold in the European cannabis market and a leg up on rival businesses.

The terms of the deal call for Curaleaf to pay $286 million up front, with 85% in Curaleaf stock and 15% in cash.

The transaction includes another $57 million dependent on achieving certain performance targets, meaning the deal ultimately could total up to $343 million.