June 9 (Reuters) - European shares gave up early gains on Tuesday to close lower for a third straight session, dragged down by commodity-linked stocks as investors assessed the fragility of the ceasefire between Iran and Israel.

The pan-European STOXX 600 index fell 0.5 percent to 618.64 points, with mining and energy stocks leading the losses, after the former fell 2.5 percent and the latter 2.4 percent.

Sentiment regarding the conflict in the Middle East remained cautious. US Energy Secretary Chris Wright said that shipping traffic through the Strait of Hormuz was increasing "very significantly."

Hopes for a sustained de-escalation were dimmed after Israel bombed the historic southern Lebanese port city of Tyre on Tuesday, killing at least eight people.

Tehran warned on Monday that it would resume hostilities if Israel continued its attacks on its ally, Hezbollah, in Lebanon.

Craig Cameron, portfolio manager at Franklin Templeton, said, "Markets have remained in a steady pattern over the past two weeks, with what's happening in the Middle East and the lesser impact of some AI-driven volatility we're seeing in Asian and US markets."

Shares of European technology companies, which have seen waves of volatility recently, showed signs of stabilizing early in the session, but closed down 1.3 percent, tracking their Wall Street counterparts.

However, the sector is still on track to achieve its strongest quarterly gains on the Stoxx 600 index.

Regarding corporate moves, the Italian financial sector remained in focus after Monte dei Paschi di Siena received competing takeover bids from Intesa Sanpaolo and Banco BPM, as the two banks competed for market share in the Eurozone banking sector.

Shares in MBS Bank rose 2.6 percent, while shares in Banco BPM and Intesa each increased by about one percent.

The European Central Bank is widely expected to raise interest rates by 25 basis points on Thursday amid ongoing concerns about inflation, although investors will be closely watching for any guidance on how far policymakers might go in this regard.

Among other sectors, telecom stocks fell 2 percent, with Ericsson and Nokia among the biggest losers on the Stoxx 600 after traders cited a report warning of potential risks from Nvidia's development of technology for future mobile networks.

Shares in defense companies fell 0.7 percent after Morgan Stanley downgraded its rating on European defense stocks to "balanced" for the first time in more than two years, citing a downward adjustment to earnings.