Aug 20 (Reuters) - The following bids, mergers, acquisitions and disposals were reported by 8:00 p.m. GMT on Tuesday:
** Barnes & Noble Inc's founder pulled the plug on his plan to buy the company's bookstores. Leonard Riggio, the company's chairman, founder and top shareholder, said he has suspended his efforts to make an offer for B&N's retail business but reserves the right to pursue an offer in the future.
** A foundation belonging to Russian tycoon Suleiman Kerimov has raised its stake in the world's largest potash producer, Uralkali, to 21.75 percent from 17.2 percent, the company said.
** Russia's Mechel said it is selling a loss-making Ukraine steel plant to its previous owner for 2,000 euros ($2,700) plus the settlement of tens of millions of dollars of debt as it pushes ahead with the disposal of non-core assets.
** Deutsche Wohnen offered to buy rival residential landlord GSW Immobilien for 1.8 billion euros ($2.3 billion) to expand in Berlin's booming rental market and tap nascent interest from international investors.
** Infinium Capital Management is in talks to acquire a strategic partner, the president of the high-speed U.S. trading firm said.
** German reinsurer Hannover Re said it was in talks to acquire a minority stake in life insurer Heidelberger Leben, which Britain's Lloyds Banking Group is selling as part of plans to exit overseas markets.
** Argentine businessman Eduardo Elsztain is in talks with bondholders of IDB Holding to invest 770 million shekels ($216 million) in the debt-strapped conglomerate's subsidiary IDB Development in exchange for a 50.5 percent stake.
** KKR & Co LP and Warburg Pincus LLC are among the private equity firms competing for Mitchell International Inc, a car and property claims software company that could fetch up to $1.5 billion, according to four people familiar with the matter.
** Two of the three bidders short-listed to buy 315 bank branches from Royal Bank of Scotland have called for the long-running sale process to be completed as quickly as possible, with one describing the outlets as "slightly neglected" under their current ownership.
** Fiberweb, a manufacturer of industrial and construction metals, said it has received a takeover proposal from Polymer Group Inc, which has been given until Sept. 17 to formalize a bid or walk away.
** Straumann Holding Ltd, the world's largest maker of dental implants, could spend over $400 million on buying cheaper rivals, signaling a desire to grab back market share from low-cost competitors.
** BHP Billiton does not have any targets for asset sales as the company has strengthened its balance sheet, but it has held discussions with potential partners for its Jansen potash project, its chief executive said.
** The National Shipping Co of Saudi Arabia has signed a memorandum of understanding with Saudi Aramco and Singapore's Sembcorp Marine to conduct a feasibility study for a maritime yard project in the kingdom.
** Poland's largest refiner PKN Orlen aims to buy petrol stations in Germany to expand its network in Europe's biggest economy, the chief of PKN's German business told a newspaper.
** Hungary's government will offer to buy back the loss-making steel maker Dunaferr from Ukraine's ISD group, to prevent a layoff of 1,500 workers planned by the company, Economy Minister Mihaly Varga said on Monday.
** Austrian fireproof materials maker RHI plans to buy magnesite mining rights in Turkey to expand its own supply of raw materials, it said late on Monday.
** Turkish conglomerate Sabanci Holding said it was not interested in buying a stake in Telekom Srbija, denying earlier media reports.