NewWall Street slightly off as dollar while margin rules tightening in China depresses market

The US dollar on Thursday hit its highest against the yen since 2002 while stocks fell after Chinese brokerages tightened margin rules and the IMF head played down talk of an imminent deal to keep Greece afloat.
US crude oil futures edged up but were on track for a weekly decline following 10 weeks of gains.
A Greek government official had sparked speculation late on Wednesday that a deal to aid Athens had been drawn up. But a string of denials by top European officials was followed by one from the head of the International Monetary Fund, Christine Lagarde, as G7 leaders met in Germany.
"We are all in the process of working towards a solution for Greece, and I would not say that we already have reached substantial results," she said in an interview on German television.
"Things have moved, but there is still a lot of work to do," Lagarde said, adding she believed Greece would fulfil its commitments.
Stocks fell on Wall Street, tracking declines in Europe on worries over Greece, though they were off the session lows. In China, indexes plummeted 6 per cent after more brokerages tightened margin trading requirements in a move seen aimed at curbing risks in a red-hot equity market.