July 31 (Reuters) - BP on Friday launched a formal sale process for its North Sea business as new Chief Executive Officer Meg O'Neill accelerates a sweeping portfolio overhaul aimed at cutting debt and simplifying the oil major.

A day earlier British Prime Minister Andy Burnham said he planned to take a "pragmatic" approach to developing and using oil and gas resources in the North Sea, setting out his position after U.S. President Donald Trump said the basin would be opened up.

"The North Sea remains integral to the UK's energy system. However, as we focus our portfolio and direct capital to our highest-value opportunities, we believe our North Sea business will be better positioned as part of another company," O'Neill said in a statement.

BP has worked in the North Sea for more than six decades and operates five major production hubs in the region, including the Clair oilfield, the largest on the UK continental shelf.

The company has stepped up its efforts to reduce debt, boost profit and refocus on its oil and gas businesses after scaling back its investment in renewable energy.

Since O'Neill took over in April, BP has reorganised into two business segments - upstream and downstream - from three, a change that took effect this month.

An internal email seen by Reuters on Thursday also disclosed BP's plans to reduce its workforce by 700.