* Euro zone blue chip index down 0.1 pct
* Banks Intesa, UniCredit weigh on Milan index
* Lanxess boosted as Warren Buffet buys stake (Adds details, updates prices)
By Danilo Masoni
MILAN, May 29 (Reuters) - European shares inched lower in quiet trading on Monday with Italian stocks left behind as worries over possible early elections weighed, hitting banks.
Activity was reduced as holidays in major markets such Britain and the United States kept investors away.
The index of the top 50 euro zone stocks slipped 0.1 percent, while Italian blue chips fell 1.1 percent, on track to end at their lowest close in over three weeks, while Germany's DAX added 0.1 percent.
Weekend reports that Italy's main parties could converge on a proportional electoral law pointed to growing chances of an election in the autumn, possibly leading to no clear majority.
In an interview on Sunday, former Prime Minister Matteo Renzi said an accord on a proportional voting system was possible though it could result in a coalition government that may have trouble holding together.
"The risk of early elections has suddenly increased to 60 percent," LC Macro Advisers founder Lorenzo Codogno said. "A hung parliament is thus the most likely outcome".
Italian banks, already hit by worries surrounding the rescue of two ailing regional lenders Popolare di Vicenza and Veneto Banca lenders, fell 1.8 percent, dragging euro zone banks down 0.4 percent.
Among Europe's heavyweight lenders, Italy's Intesa Sanpaolo and UniCredit both fell more than 1.7 percent, while Deutsche Bank slipped 0.2 percent and Banco Santander added 0.1 percent.
Spanish-listed shares of International Airlines Group , the parent company of British Airways, fell 2.7 percent. British Airways flights suffered massive disruptions over the weekend with over 1,000 flights cancelled after a computer system failure.
Lanxess rose more than 3 percent, leading gainers on the STOXX after news that billionaire Warren Buffett had acquired a 3 percent stake in the German chemicals maker. (Reporting by Danilo Masoni and Vikram Subhedar)