European stocks opened with a cautious tone Wednesday as ongoing political concerns in the region continued to offset underlying corporate and economic fundamentals.

The region-wide Stoxx Europe 600 Index, the broadest measure of equity market performance, was marked 0.42% higher by 08:30 GMT even as major indices around the region were hovering little-changed from Tuesday's closing levels.

Britain's FTSE 100 drifted about 6 points lower in the opening 30 minutes despite better-than-expected full-year earnings from Rio Tinto plc (RIO) - Get Report .

Rio posted stronger-than-expected full year earnings Wednesday and boosted its annual divided as the world's second-largest miner took full advantage of rising commodity prices.

Full year net profit came in at $5.1 billion, the company said, up from a loss of $866 million in 2015 and ahead of analysts' forecasts of $4.87 billion. The group will pay a full year dividend of $1.7 per share, down from 2015's $2.15 payout but firmly ahead of the higher end of market forecasts and will also buyback $500 million worth of shares.

Rio shares rose 2.66% by 08:30 GMT, leading FTSE gainers and extending their three month advance past 23%.

Germany's DAX index rose 0.06% while the CAC-40 in Paris added 0.32%, helped by solid gains for construction group Vinci SA and drugmaker Sanofi SA.

Political risk, however, was once again dominating market trading, with the euro extending Tuesday's decline with a 0.32% decline against the U.S. dollar to 1.0647 and safe-haven German bund yields falling 1 basis point to 0.34%.

Greece's government bond yields were also in focus, as benchmark 2-year borrowing costs spiked past 10% -- levels not seen since the country narrowly averted being chucked out of the single currency back in the summer of 2015 -- amid persistent concern that promises linked its €85 billion bailout are not being adhered to in Athens.

Overnight in Asia, stocks rallied in the latter half of the session to end the trading in the green, with the Nikkei 225 rising 0.51% and passing the 19,000 mark for the week's first gain. The region-wide MSCI Asia ex-Japan index was marked 0.18% higher after a 0.5% advance for Australia's S&P/ASX.

The U.S. dollar traded stronger overnight, as well, rising for the fifth consecutive session on renewed bets of a Federal Reserve rate increase in March and safe-haven flows from unsteady currencies in Europe and China. The dollar index, a measure of the greenback' strength against a basket of six major trading partners, was marked 0.07% higher at 100.43.

Oil prices extended declines from Tuesday's trading after the American Petroleum Institute reported a bigger-than-expected buildup in U.S. crude stocks, which the group said rose by 14.2 million barrels, the most in three months. WTI futures for March delivery were marked 0.8% lower at $51.72 per barrel while Brent crude contracts for the same month, the global benchmark, were trading 0.45% lower at $54.79.

The Dow Jones Industrial Average pared earlier gains but jumped 0.19% to finish at 20,090, well off a new intraday record high of 20,155. The Nasdaq also gained 0.19%, posting a new record close of 5,674. The S&P 500 struggled for direction, closing up just 0.02%.

Oil prices in the U.S. Tuesday settled down 1.6% to $52.17 a barrel, dragging the energy sector down. Shares of Chevron (CVX) - Get Report declined 1.4%, Anadarko Petroleum (APC) - Get Report dropped 2.9% and Occidental Petroleum (OXY) - Get Report fell 2%.

U.S. futures prices suggest a stronger day on Wall Street, with the Dow rising 13 points, a 0.5 point gain for the S&P 500 and a 1.2 point bump for the Nasdaq.