GABORONE, May 29 (Reuters) - Botswana is hoping for a quick separation of De Beers from the Anglo American Plc group before the UK-listed diversified mining giant is exposed to a possible hostile takeover, President Mokgweetsi Masisi said on Wednesday.

Botswana, the world's top diamond producer by value, is finalising a new ten-year gem sales deal agreed last June with De Beers. The two parties had agreed to finalise the deal by June 28 this year, but the proposed takeover of Anglo by the BHP Group has brought uncertainty to the sales agreement.

Anglo has rebuffed BHP and on Wednesday rejected the Australian company's request for more time to discuss its latest $49 billion takeover offer.

Anglo plans to divest from De Beers and its other coal, nickel and platinum assets to focus on energy transition metal copper.

Masisi said he would meet Anglo and De Beers executives at jewellery industry trade event the JCK Show in the United States this week.

“One thing we don’t want is a hostile owner. We are watching this very closely because whoever buys Anglo, if it is sold, will then be the owner of De Beers and De Beers is our strategic partner with whom we are at the tail end of our negotiations,” Masisi told reporters as he departed for the United States.

Botswana is a 15% shareholder in De Beers and accounts for 70% of the company's annual rough diamond supply.

The renewal of the sales deal and mining rights for Botswana and De Beers' joint venture mining company, Debswana, is vital to the southern African country, which gets about 40% of its revenue, 75% of its foreign exchange earnings and a third of national output from diamonds.

“We have received some assurances and the reason for travelling is to go and get that first hand from the principals of Anglo and De Beers that they are committed to separating De Beers from Anglo before Anglo is sold, if it is sold,” Masisi said.

Botswana needs to finalise the deal with De Beers so that it can begin to benefit from the renegotiated terms agreed in June 2023, which include a higher allocation of rough diamonds from Debswana to the state-owned Okavango Diamond Company (ODC) and a $750 million investment by De Beers into other economic sectors over the next ten years. (Reporting by Brian Benza; Editing by Nelson Banya and Mark Potter)