April 19 (Reuters) - The following bids, mergers, acquisitions and disposals were reported by 1000 GMT on Wednesday:

** A group backed by private equity firm KKR & Co said it had made a revised A$6.15 billion ($4.65 billion) offer for Australia's biggest lottery operator Tatts Group Ltd , upping the ante in a bidding war against Tabcorp Holdings Ltd.

** Chevron Corp, the second-largest U.S.-based oil company, sold its Canadian gasoline stations and refinery in British Columbia to Parkland Fuel Corp, a marketer of petroleum products, for C$1.46 billion ($1.09 billion).

** Ant Financial, the payment affiliate of Alibaba Group Holding Ltd, has acquired Singapore-based payment service helloPay Group, part of the Chinese firm's drive to boost its Alipay brand and presence in Southeast Asia.

** A Japanese government-backed fund and policy bank are considering a joint bid with Broadcom Ltd for Toshiba Corp's semiconductor business, a move that would vault the U.S. chipmaker into the lead to buy the prized unit, the Asahi newspaper said.

** Siam Commercial Bank (SCB) has entered into exclusive talks with Hong Kong insurer FWD Group to sell its life insurance arm, which could raise $3 billion for Thailand's third-biggest lender, people with direct knowledge of the matter said.

** The Saudi-based Islamic Development Bank (IDB) plans to take at least a 10 percent stake in Turkey's state-run stock exchange as the multilateral lender ramps up activities in the country, a senior official of the bank told Reuters.

** Akzo Nobel, the Dutch paint maker trying to fend off a 24.6 billion euro ($26 billion) takeover by U.S. rival PPG Industries Inc, outlined an alternative plan to separate its chemicals business and pay shareholders 1.6 billion euros in extra dividends this year.

** British materials testing company Exova Group said UK-based Element Materials Technology would buy it in a deal valued at 620.3 million pounds ($795.3 million).

** Dutch eyeglass store operator Grandvision said it will acquire Tesco's chain of more than 200 opticians.

** Centurion Midstream Group LLC said it acquired a petroleum marketing and transportation business that operates in West Texas from Agave Energy Holdings, a subsidiary of Lucid Energy Group.

** India's online grocery delivery service BigBasket and smaller rival Grofers India Pvt Ltd have begun talks on a possible merger, Indian newspaper Mint reported, citing sources.

** Sweden's SCA has rejected a recent bid for its hygiene arm and an offer last year for its forestry business, Swedish daily Dagens Nyheter reported, citing sources.

** Top shareholder Invesco Perpetual has trimmed its stake in technology incubator Allied Minds for the second time in as many weeks, according to regulatory filings.

** An Italian regulator ordered French media group Vivendi on Tuesday to cut its stake in either Telecom Italia or broadcaster Mediaset within a year, ruling it was in breach of rules designed to prevent a concentration of power.

** Renova Energia SA sold a wind farm project to a unit of AES Corp for 600 million reais ($193 million) on Tuesday, enabling the Brazilian renewable power company to replenish cash amid a severe cash crunch.

** Verizon Communications Inc has agreed to buy optical fiber from Corning Inc for at least $1.05 billion over the next three years as the No. 1 U.S. wireless carrier aims to improve its network infrastructure, the companies said on Tuesday. (Compiled by Ahmed Farhatha in Bengaluru)