Widebody Transport
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 1.0
Situational Awareness
ATC Issue All Types; Deviation - Speed All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued New Clearance; General Work Refused
Company Policy; Chart Or Publication
I gave Aircraft X a clearance to cross the arrival fix at 11;000 feet and he already had a speed of 310 knots or greater. When he was around 15;000 feet he said he was reducing speed to 250 knots. I told him to maintain 300 knots. I asked him if it was an aircraft performance requirement. He said it was company policy to reduce speed to 250 knots at 11;000 feet. I told him we have a coordinated speed with Approach to be at 11;000 feet and 300 knots and that he needed to maintain 300 knots. He said unable reducing speed to 250 knots due to company policy 'I can't help it'. I then told the Supervisor; then coordinated the situation with Chicago Approach.There was an aircraft that was about 10 miles behind Aircraft X at the time with the same crossing that I then needed to descend below Aircraft X. As a result I read Aircraft X the Brasher Warning and gave him Chicago Center contact information. I am not sure where it went from there. We have been having this problem for a while now with overseas pilots abiding by company policy and reducing speeds to 250 knots sometimes with no warning disregarding ATC clearances.I believe this is a big enough issue to look into oversees policies on this type of situation and correct it before someone loses separation or worse. Luckily I was slow at the time; but with a big enough trail into the airport a situation like this can cause us to now start vectoring because of an aircraft slowing without warning.
ZAU Center Controller reported a foreign air carrier refused to comply with a speed assignment.