Shares in BP jumped 8 percent on Wednesday, helped by bid talk and optimism that the worst may be over for the stock as the company comes closer to halting the massive oil leak from its Gulf of Mexico well.

BP is up on spill-over interest from the JPMorgan 'Fantasy M&A' note yesterday mentioning possible bids, but really it's just a squeeze after the falls, said a trader, referring to a research note which speculated Exxon Mobil could buy BP.

BP has lost $100 billion in value since its Deepwater Horizon drilling rig sank on April 22.

In recent days BP has been flagging that a well being drilled to kill the leaking well is closing in on its target. Analysts have been saying for weeks that if BP halts the leak, this could lead to a rebound in the shares.

(Reporting by Atul Prakesh, Jon Hopkins and Tom Bergin; Editing by Erica Billingham)