* Supply snafus knock Siemens Energy wind unit; shares plummet

* Rio Tinto tumbles as Serbia vetoes $2.4 bln lithium plan

* Miners retreat from 2008 highs

* Automobile stocks worst weekly performers

Jan 21 (Reuters) - European stocks slumped on Friday to mark a third week of losses as jitters over monetary policy tightening by central banks this year and weak economic data sparked steep declines across global equities.

The pan-European STOXX 600 dropped 1.8%, and was down 1.4% over the week. Mining stocks were the day's worst performers, losing 3.3%.

Anglo-Australian miner Rio Tinto tumbled 2.2%, the biggest drag on the sector, after Serbia revoked its lithium exploration licenses over environmental concerns, hurting the group's ambition to become Europe's largest supplier of the metal.

Investors are now waiting for the U.S. Federal Reserve's meeting next week for details on how it intends to tackle high inflation.

"There's a lot of speculation - four, five, six U.S. rate hikes this year, a 50 basis point hike in March - which has fed markets' underlying anxiety," said Craig Erlam, a senior market analyst at OANDA.

"We can never underestimate the knock-on effects of the U.S. on global markets, and Europe is facing challenges of its own with the Omicron variant and energy crisis," he said, adding that markets were even starting to price in potential tightening by the European Central Bank (ECB).

Cementing those concerns, ECB accounts showed policymakers argued at a meeting last month that inflation could "easily" get stuck above target, and the central bank should keep the door open to tightening policy.

Further, euro zone consumer prices jumped at a record pace in December, boosted by a surge in energy prices and supply chain bottlenecks.

Adding to worries, the Bank of England will press ahead with its tightening cycle next month as red-hot inflation runs well ahead of target, a Reuters poll found.

However, at some point, investors will start to be drawn back in towards European markets once the peak inflationary period of late first-quarter, early second-quarter passes, and economic data starts to improve, Erlam said.

Airbus lost 2.0% after saying it had canceled a contract with Qatar Airways for 50 A321neo jets, broadening a $600 million-plus dispute with the Gulf carrier over the larger A350.

Siemens Energy plunged 16.6% after cutting its forecast as wind unit Siemens Gamesa warned of prolonged supply chain issues, renewing pressure on the German firm to fully take over the unit.

Siemens Gamesa dropped 14.0%, joining Siemens Energy as the two worst performers on the STOXX 600.

Concerns over supply chain disruptions also saw European automobile stocks lag their peers this week, down 4.2%. (Reporting by Anisha Sircar in Bengaluru; Editing by Subhranshu Sahu, Kirsten Donovan)