TEHRAN, Oct. 25 (ISNA)-Iran's permanent envoy to the UN, Mohammad Khazaei, in his recent letter to the UN Secretary General, Ban Ki-moon, said Iran regards Britain responsible for Mojahedin Khalq Organization's (MKO) crimes in the regional and cross-regional countries.

The letter circulated as the UN Security Council document seriously condemns Britain's removal of the name of (MKO) from its terrorist black list.

If Britain's failure in fulfilling legal commitments causes security losses for Iran, the country is entitled to take legal measures to make up for them, the letter says.

The terrorist group has launched series of expanded terrorist attacks against Iranian nationals and politicians during past years and caused many financial and spiritual losses.

Even now members of the group preserve their military and army powers and are keeping on money laundering, armed conflicts and brutal measures.

In spite of the organization's clear terrorist activities, British government has ignored the undeniable evidence confirming the group is trying to reconstruct its military structure, he wrote in the letter as adding there is no sign suggesting the group has curbed violent activities.

Such evidence has also been corroborated by British high legislative and administrative officials.

The letter also calls Britain's move "questioning, unacceptable and illegal" which is against the country's international obligations regarding campaign against terrorisms and the UN Security Council's 1373 and 1624 resolutions.

British government's measure has legitimated the terrorism and the group's terrorist activities, Khazaei added.