Aussie shares gain on boost from Sydney Airport, energy and materials stocks

* Energy and the materials sector lead gains

* Sydney Airport receives raised takeover proposal

* NZX 50 ends down 0.05% (Updates to close)

Sept 13 (Reuters) - Australian shares rose on Monday, boosted by airport operator Sydney Airport Holdings surging on an improved takeover bid and solid gains in the energy and materials stocks.

The S&P/ASX 200 index rose 0.25% to close at 7,425.2 after rising as much as 0.4% earlier, as financial stocks fell amid signs of higher inflation in the U.S. financial markets. The benchmark ended 0.5% higher on Friday.

Sydney Airport Holdings advanced as much as 5.1% to its highest in over a year after bidder Sydney Aviation Alliance increased its offer price to A$8.75 from prior proposals at A$8.45 and A$8.25, to acquire all shares in the airport operator.

“The benchmark rose for a second day but closed below session highs due to pressue from the U.S. market as it struggles with an unfavourable mix of weak growth and strong inflation. Stagflation and tapering with new pandemic worries is a bad mix for the economy,” said Mathan Somasundaram, chief executive officer at Deep Data Analytics.

The financial sector dipped 0.1% with National Australia Bank dipping 1% after an analyst downgrade, and Westpac easing 0.04%.

Bucking the trend, energy stocks rose 1.25% after oil prices hit a one-week high on concerns over U.S. supplies, along with higher demand hopes.

Natural gas major Santos Ltd led gains on the sub-index, advancing up to 3.1%, followed by heavyweight Woodside Petroleum Ltd, gaining 1.9%.

Major miners rose 1.06% led by lithium-boron supplier Ioneer Ltd, up 7.58%, followed by lithium miner Pilbara Minerals Ltd, gaining 7.32%.

The uranium sub-sector also gained after spot prices hit a seven-year high as demand has been reignited by the push for cleaner, greener fuels. Uranium producer Deep Yellow advanced 28.8%, hitting highest in over eight years.

New Zealand’s benchmark S&P/NZX 50 index slipped 0.05% to end at 13,064.4. (Reporting by Riya Sharma in Bengaluru; Editing by Rashmi Aich)