A House of Lords Committee says legislation to reduce the levels of discarded fish at sea isn't working.

The so-called "landing obligation" came into full force on January 1 this year.

But the Lords' European Union Committee says it appears to have had limited effect in the first six months.

Only small quantities of fish that would previously have been discarded have been landed.

They're calling for "robust mechanisms" to be put in place to monitor and enforce compliance.

Committee Chair Lord Teverson said, "The evidence is that nothing very much is happening. We are not having undersize fish landed in any quantity at ports, there have been very few if any, prosecutions so the evidence suggests that not a lot has changed in the first six months".

But Scottish fishing leaders have reacted angrily to the findings.

Bertie Armstrong, the Chief Executive of the Scottish Fishermen's Federation, said Scottish fishermen had done everything they could to comply with legislation.

They'd also introduced a whole series of technical measures to prevent catching unwanted fish.

But he said it would only be after Brexit that discards could be properly addressed by the industry.

Discards came about as a result of the European Common Fisheries Policy.

But quotas meant healthy fish were thrown overboard.

It's estimated that prior to the introduction of the landing obligation in 2013 1.7 million tonnes were discarded in EU fisheries every year.

It was phased in gradually from 2015 and has been implemented fully over the past six months.

The Lords Committee says it was expected to result in an increased volume of undersized fish being brought ashore but this hasn't happened.

It says enforcement agencies are taking a range of actions in an attempt to monitor compliance with the landing obligation. However none of the currently-used mechanisms are sufficient to determine levels of non-compliance or to provide sufficient evidence for enforcement action.

It's suggested the use of remote electronic monitoring is the only way to monitor compliance.

The Scottish Government say they support the landing obligation where good, valuable fish are not thrown back dead and they will enforce any breaches they encounter.

They've welcomed the report and say they'll study the findings in more detail.