Under the pending agreement, China must agree to prevent unfairly low prices for the launching services.

January, he was prevent prices from rising more than one percent and control of the rice price and freeze.

However, over the longer term, even buying in advance can't prevent higher prices feeding through into bills.

Arab oil producers appear determined to prevent prices from rising substantially above the $18 level.

But the slowdown did not prevent prices from escalating.

In that way, the Government tries to prevent surpluses and resulting plunging prices.

Controlling these prices responds to the need to prevent prices from becoming too high.

Mr. Cochrane said he thought market forces would prevent prices from collapsing below $10.

We have heard it said many times in this Parliament that markets should be opened up in order to prevent prices rising.

"But the buying by the shorts wasn't sufficient to prevent prices from tumbling once again toward evening."