European shares closed mixed on Wednesday, despite a surge in Alstom stocks after they reopened for trade.
Central banks eyed
The pan-European provisionally closed down around 0.1 percent on Wednesday at 1,351.76 points, as inflation data for the euro zone came in worse than expected and U.S. growth data disappointed.
Tensions in Ukraine also continued to trouble investors. However, both the and German unofficially closed up 0.2 percent.
European markets
Euro zone inflation picked up in April, but remained below expectations, maintaining pressure on the European Central Bank (ECB) to stimulate the economy after its next monetary policy meeting.
Consumer prices rose by 0.7 percent year-on-year in April, according to official statistics released by Eurostat Wednesday, marking an uptick from March's 52-month low of 0.5 percent.
Read MoreEuro zone inflation picks up in April
U.S. stocks wavered between mild gains and declines on Wednesday, as investors awaited a policy decision from the Federal Reserve and weighed economic reports that suggested growth stalled in the first quarter, but that employers added more workers than expected in April.
Meanwhile, the Bank of Japan on Wednesday kept monetary policy steady, a move that underscored its confidence that the country's economy remains on track. As expected, it also maintained its pledge to increase its monetary base by 60-70 trillion a year. Asian markets remained mixed after the news.
Read MoreBank of Japan stands pat, focus on semi-annual report
Ukraine fears
Tensions in Ukraine continued to weigh on investor sentiment. On Wednesday, masked gunmen seized government offices in another Ukrainian town.
Furthermore, the International Monetary Fund cut Russia's growth forecast for the year to 0.2 percent from 1.3 percent, adding that Russia was currently "experiencing recession."
Read MoreIMF slashes Russia growth forecast, warns of outflows
Alstom soars
In corporate news, Alstom shares soared 9.3 percent on reopening after last week's suspension. The French group said Wednesday it was considering General Electric's (GE) $13.5 billion bid for its energy unit.
Read MoreAlstom mulls $13.5billion GE bid, Siemens stands by
Shell shares climb
Shares of French bank BNP Paribas slipped 3.2 percent, despite it posting a forecast-beating 5.2 percent rise in net profit for the first quarter. It warned of larger-than-expected litigation fees however.
Read MoreBNP Paribas profit beats, warns of legal charges
Royal Dutch Shell reported Wednesday that its first-quarter earnings almost halved from a year ago to $4.5 billion, citing impairments related to refineries in Asia and Europe. Shares were higher by 3 percent, however, with analysts highlighting a continued turnaround at the oil major.
Read MoreShell earnings fall on refineries impairments
Meanwhile, U.K. oil company Heritage announced it had agreed to a takeover offer from a Qatari investment fund for $1.3 billion; shares soared by 22 percent on Wednesday.
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