Greece's rejection of bail-out austerity conditions and weak Chinese trade data prompted stockmarket declines around the world, as the future of the euro zone comes under scrutiny.
Greece's new Government wants to unravel some of the austerity measures which are part of its 240 billion ($NZ366.9 billion) bail-out programme, and has also called for a bridging loan programme from international creditors, which has so far been ruled out by the euro group lenders.
Craigs Investment partners broker Peter McIntyre said stocks in the United States extended losses towards the end of the trading day, with investors ''remaining jittery'' following disappointing trade data from China and the unfolding ''Greek debt drama''.
''European stocks kicked off the week with losses, as investors fretted over the intensifying standoff between Greece's new Government and the European Union, as well as the disappointing Chinese trade data,'' he said.
Greece's new Prime Minister Alexis Tsipras was elected on the back of opposition to austerity measures which have brought to country to its knees.
The Dow Jones industrial average closed down 0.53%, at 17,729.21; the S&P 500 was down 0.42%, at 2,046.74; and the Nasdaq composite was down 0.39%, to 4726.01.
In Europe, the FTSEurofirst 300 index of top regional shares ended 0.73% lower, at 1480.01 while the MSCI's all-country world stock index fell 0.39%, to 418.86. Japan's Nikkei was up 0.36% at 17,711.9 and Hong Kong's Hang Seng was down 0.64% at 24,521.
Forsyth Barr broker, Andrew Rooney, said US stocks declined with concern Greece's rejection of the bail-out terms could cause a default.
The Greek Prime Minister had vowed on Sunday to negotiate an end to the austerity measures, fuelling concern over a confrontation with Greece's international creditors, Mr Rooney said.
On Sunday, data revealed China's exports fell 3.3% in January, compared with a year ago, while its imports tumbled 19.9%, raising concerns about the world's second-largest economy.
Mr McIntyre said both the import and export data declines were unexpected, suggesting there were more negative risks facing the Chinese economy.
Wall Street and European shares slumped a day after Mr Tsipras ruled out extending the country's bail-out and said he would reverse some of the reforms imposed by its lenders, raising fears of a Greek exit from the euro zone, Reuters reported.
Tensions rose further on Monday after European Commission President Jean-Claude Juncker said Greeks should not expect the euro zone to accept the latest terms proposed by Greece. Greek banking shares tumbled nearly 10%.
''Greece can't spend more money, back-track on labour market reforms and stay in the euro,'' Michael Jones, chief investment officer at RiverFront Investment Group in Richmond, Virginia, said.
Violence in Eastern Ukraine also weighed on shares. US President Barack Obama said on Monday his administration was examining all options in handling the crisis in Ukraine, but he has not yet decided whether the United States would provide arms to Kiev.
