* Pan-European FTSEurofirst 300 index up 0.1 pct
* Adidas rises after FIFA president resigns
* Amadeus slips on Lufthansa ticket surcharge
* Market awaits ECB decision, news on Greece (Adds detail, quote)
By Atul Prakash and Alistair Smout
LONDON, June 3 (Reuters) - European shares edged higher on Wednesday, with supermarket groups Ahold and Delhaize advancing after media reports suggesting merger talks between the two could come to a successful conclusion as early as June.
Shares in Ahold and Delhaize rose 3.5 percent and 6.2 percent respectively. The two companies are in talks to create a top 20 global retailer with a major presence in the United States. A deal would see a combined retailer worth around 23 billion euros ($25.60 billion).
The pan-European FTSEurofirst 300 index was up 0.1 percent at 1,574.31 points by 0959 GMT after falling 0.9 percent in the previous session. The index is still up about 15 percent so far this year.
Germany's DAX advanced 0.5 percent, led by a 1.3 percent rise in Adidas after FIFA President Sepp Blatter announced he would step down in the wake of a corruption scandal that has rocked soccer's global governing body.
Adidas is a sponsor of FIFA and experts said Blatter's resignation would be a major relief for the organisation's sponsors.
On the downside, Spanish travel booking technology company Amadeus fell 6.2 percent after German airline Lufthansa said it would levy a 16-euro surcharge on tickets not booked on their website. Analysts said there were concerns that others would want to do the same.
Investors will keep an eye on the policy meeting of the European Central Bank later in the day. The ECB is widely expected to reaffirm its commitment to its trillion-euro asset purchase programme.
"The ECB is widely expected to keep policy unchanged at the June council meeting today," Ioan Smith, managing director of KCG Europe, said in a note.
"The focus of the press conference will be on comments on Greece and whether the ECB is willing to maintain Greek banks' lifeline in the form of extended ELA assistance."
Greek Prime Minister Alexis Tsipras heads to Brussels on Wednesday to meet European Commission President Jean-Claude Juncker. The spokesman for the ruling Syriza party said Greece would not make a June 5 repayment without a deal with its international creditors soon.
Greece's creditors on Tuesday drafted the broad lines of an agreement to put to the leftist government in Athens in a bid to conclude four months of acrimonious negotiations and release aid before the country runs out of money.
"Overall there is still some optimism that a deal will be struck in the end but for now uncertainty is likely to continue," Markus Huber, senior analyst at Peregrine & Black, said.
Europe bourses in 2015: link.reuters.com/pap87v
Asset performance in 2015: link.reuters.com/gap87v
Today's European research round-up
Additional reporting by Paul Day in Madrid; Editing by Gareth Jones