The rules that require ocean freight consolidators to post a $50,000 bond with the U.S. Federal Maritime Commission before being allowed to operate in the United States are likely to be amended fairly soon, Christopher Koch, FMC chairman, told industry representatives Wednesday.

Speaking in London, Mr. Koch said he was hopeful that Congress within a couple of months would approve a pending bill that would enable the commission to draw up more flexible requirements on financial responsibility for consolidators, also called non-vessel-operating common carriers.Mr. Koch would not comment on the prospects for abolishing tariff filing requirements for consolidators. The international freight forwarding community, supported by some major U.S. companies, has been waging a vigorous campaign to have the law changed, arguing that the cost of filing consolidators' tariffs adds around $25 million a year to U.S. transport costs.

The deadline for the submission of petitions commenting on the tariff- filing requirements is next Tuesday, but Mr. Koch said it was impossible to tell how long the subsequent assessment process may take before a final decision is made.

Addressing the annual lunch of the British International Freight Association, Mr. Koch stressed the importance of the United States and the European Community coordinating maritime policy.

In particular, he singled out the North Atlantic and said lines in this trade that are already losing large sums of money should not suffer further

because of inconsistent regulation.

Whether shipping conferences should set inland tariff rates is one possible area of difference between Washington and Brussels, Mr. Koch said. But he does not expect the Eurocorde agreement between conference and non-conference carriers on the North Atlantic to be a problem.

The European Commission is expected to make a ruling on the legality of Eurocorde within the next few days, and Mr. Koch said Wednesday that he believes Eurocorde "will not be disapproved" by the EC since it has neither forced freight rates up nor led to a deterioration in service quality. The FMC already has approved Eurocorde.

He also predicted that carriers on the North Atlantic that are searching for ways of improving the trade are more likely to form a new rate-setting conference rather than set up capacity-reducing arrangements.

The European Commission already has given shipping conferences and consortia a block exemption from EC competition rules, he explained, even though a stabilization agreement similar to that on the Pacific probably is less anti-competitive.

In view of the dire conditions on the North Atlantic, where carriers are expected to lose some $250 million this year, Mr. Koch said shippers were being unrealistic to demand greater competition. Instead, he urged the two sides to "break down the barriers" and try to develop a more constructive dialogue.