The ASX has had a bleak start to the week with most shares down in morning trade, excepting the energy and telco sectors.

The benchmark S&P/ASX200 index was down 35.1 points, or 0.52 per cent, to 6,698.4 points at 1200 AEDT on Monday, with the broader All Ordinaries down 34.2 points, or 0.50 per cent, to 6,821 points.

The share market’s downcast performance was expected given concerns on Wall Street over tensions in the Middle East and weak US manufacturing sector data.

The US’ killing of an Iranian military commander in Iraq last week shook confidence and boosted oil prices.

On the Aussie market, financial shares were most affected and recorded a 1.1 per cent drop.

National Australia Bank was the hardest hit of the big four backs and lost 28 cents, or 1.13 per cent, to $24.44.

Commonwealth Bank saw a drop of 88.50 cents, or 1.1 per cent, to $79.425, while ANZ lost 26 cents, or 1.05 per cent, to $24.47.

Westpac lost 19.50 cents, or 0.8 per cent, to $24.165.

Insurers were also among the losers.

Insurance Australia Group lost 17 cents, or 2.23 per cent, to $7.44.

QBE had a drop of 21 cents, or 1.62 per cent, to $12.75.

It was a different story in the energy sector.

Santos was the best performer and gained 16 cents, or 1.9 per cent, to $8.57.

The telco sector was held up by Telstra, which gained one cent, or 0.28 per cent, to $3.60.

The Australian dollar is buying 69.53 US cents, down from 69.63 US cents on Friday.