* Allianz consortium to pay around 3.5 billion euros - sources
* Tank&Rast to strengthen Allianz's infrastructure exposure
* Atlantia , CIC, Macquarie trumped - sources (Adds confirmation of deal, details)
FRANKFURT, Aug 3 (Reuters) - A consortium led by insurer Allianz ALVG.DE will buy German motorway service station group Tank&Rast for an undisclosed sum, the insurer said on Monday.
Two sources familiar with the deal said the group is paying around 3.5 billion euros ($3.84 billion).
"The acquisition is an important step in our ambition to substantially grow our portfolio of high-quality infrastructure companies and to diversify across sectors and countries," said Christian Fingerle, chief investment officer responsible for infrastructure investments at Allianz Capital Partners.
The consortium includes Munich Re's MUVGn.DE MEAG unit, sovereign wealth fund Abu Dhabi Investment Authority and Borealis, part of pension fund OMERS.
It beat offers from groups including Italian motorway operator Atlantia ATL.MI , Chinese sovereign wealth fund CIC CIC.UL and Australian infrastructure investor Macquarie MQG.AX , sources familiar with the deal said. ID:nL5N1034CP
Tank&Rast, which operates 350 petrol stations and 390 service stations, is being sold by buyout group Terra Firma TERA.UL and Deutsche Asset & Wealth Management, part of Deutsche Bank DBKGn.DE .
Terra Firma bought Tank&Rast for 1.1 billion euros in 2004, before selling 50 percent to Deutsche in 2007.
Banking sources said on Monday banks had lined up 1.45 billion euros of loans to back the acquisition, and that financing totalled around 7.8 times Tank & Rast's EBITDA. ID:nL5N10E2RL
Tank&Rast reported earnings before interest, tax, depreciation and amortisation (EBITDA) of 236 million euros in 2014 from 235 million a year earlier. The company had nearly 800 employees at the end of last year.
Morgan Stanley (NYSE:MS) advised the Allianz consortium on the deal, while Bank of America (NYSE:BAC) and BNP Paribas (PARIS:BNPP) led the financing of the transaction.
Terra Firma, run by British financier Guy Hands, was advised by Deutsche Bank and JP Morgan.
($1 = 0.9112 euros)