The pan-European STOXX 600 index inched up 0.1% by 0715 GMT, with bank and technology shares leading gains on the index, rising 1.2% and 0.8%, respectively.
Oil and gas shares were down 0.9%, tracking oil prices.
The Fed is expected to hike interest rates by 25 basis points on Wednesday but investors will remain focussed on whether the U.S. central bank indicates that it expects to pause rate increases after May.
HSBC Holdings Plc jumped 3.9% on better-than-expected tripling of quarterly profit, as rising interest rates worldwide boosted the lender's income.
Electrolux AB climbed 6.6% and was the top gainer on the index after reports of an approach from China's Midea Group for a potential acquisition of the Swedish brand.
Meanwhile, BP Plc lost 3.0% after the company pared a share buyback plan but made a $5 billion profit in the first quarter of 2023, up from the previous three months.
Investors will watch the euro zone preliminary inflation figures for April, due at 0900 GMT, for more clues on ECB's monetary tightening path.
(Reporting by Shubham Batra in Bengaluru; Editing by Varun H K)
