The FTSE was down 10.1 points, or 0.17%, to 5733.95 in early trading as the volcanic ash concerns continued to hit travel firms.
TUI Travel, which has seen its shares fall 3.9% to 282.7p, says the cost of the ongoing flight ban has so far cost the group £20m and will run at an estimated £5m-£6m each day going forward.
Thomas Cook fell 2.95% to 253.4p while British Airways dropped 2.77% to 228.5p. Easyjet and Ryanair were also lower.
Royal Bank of Scotland led the winners again after a strong session on Friday, up 4.35% to 50.40p. Lloyds Banking Group climbed 1.85% to 65.90p and BT Group was up 1.67% to 133.60p.
In the US, the charges of fraud against Goldman Sachs cast a cloud over Wall Street on Friday, with the Dow Jones tumbling 1251.91 (1.1%) to 11,018.66.
Financial shares led the stock market lower, with Goldman ending 12.79% down at $160.7. General Electric and Bank of America both reported profits which topped forecasts, but their shares still fell, down 2.7% and 5.5% respectively.
In Japan, leading shares fell sharply again on Monday, continuing last week's falls.
The main Nikkei 225 index closed down 193.41 points (1.74%) to reach 10908.77 points.
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First mentioned in Cridland Report