The pan-European STOXX 600 wobbled in early trade and was last flat at 546.93 points at 0722 GMT.
Travel and leisure fell 1.2%, with Germany’s TUI and Easyjet down over 4% each.
British low-cost airline and travel firm Jet2’s shares lost a quarter of its value after forecasting full-year operating profit to be towards the lower-end of its expectations.
Porsche slipped nearly 1% as the luxury car maker’s stock was to be relegated to the German mid-caps index following recent losses in its shares, hurt by U.S. import tariffs and weakening demand in key market China.
Caution prevailed as concerns over debt-fuelled fiscal spending by developed market governments resurfaced this week, sparking volatility in European stocks and longer-dated bonds. Later on Thursday, focus will shift to debt auctions in France and the United Kingdom, which have been at the center of Europe’s bond selloff.