The State Department, which had pledged in mid-November not to allow the chameleon-like organisation to escape US sanctions by changing its name, formally amended its regulations to list the Kurdistan People's Congress as an alias of the PKK.
The United States "has concluded that there is a sufficient factual basis to find that the Kurdistan Workers' Party, also known as the Freedom and Democracy Congress of Kurdistan and other aliases, has changed its name to the Kurdistan People's Congress (KHK)," it said in a notice published in the Federal Register.
An analyst, speaking to Aljazeera.net, said the blacklisting of the PKK would undermine the Kurdish people's struggle for sovereignty.
"The Kurdish struggle is unfortunately inextricably bound to post-colonialist struggle against that of national liberation", said Magnus Ranstorp, Director of the Centre for Studies of Terrorism and Political Violence at the University of St Andrews in the UK.
"Their struggle will be much more difficult now, even more so than that of the Palestinian struggle".
Ranstorp added that "one should separate the notion of right to self-determination to legitimacy of some acts taken in the past". "In other words", he continued, "self-determination is largely the issue".
"Their struggle will be much more difficult now, even more so than that of the Palestinian people"
Director, Centre for Studies of Terrorism and Political Violence at the University of St Andrews, UK
Inclusion on the blacklist subjects members of the group to travel and financial sanctions, including a freeze on any assets they might have in the United States or that held by institutions subject to US jurisdiction.
That, Ranstorp said would have an effect on direct activity by the group but also "certainly won't help the perception of the Kurdish nation by the outside world".
In some ways, he added, the situation was "almost an unresolvable conflict".
Ranstorp said he was not sure about the timing of the blacklisting by the US though.
"Traditionally, the PKK was the target of counter-terrorism efforts in Europe, because of its activities related to terrorism".
The PKK, in 2002, vowed to pursue
democratic means for sovereignty
The whole issue, Ranstorp added, died down, but was "eclipsed by 9/11, the abduction and trial of its leader Abd Allah Ocalan and the whole mood within US and Europe to eradicate any form of terrorism".
The Kurdistan People's Congress, the names "People's Congress of Kurdistan" and "KONGRA-GEL" , were also added to the State Department's list of foreign terrorist organizations, as well as Treasury Department blacklist.
On 12 November, the Iraq-based group, which has waged a 15-year separatist war on Ankara, announced that it was disbanding in order to set up a more democratic Kurdish organization.
But Turkish officials and observers quickly dismissed the group's move as a tactic to shrug off their violent image and ward off a possible US clampdown on their bases in northern Iraq.
Later, the group - which had already changed its name from the PKK to the Turkish Congress for Democracy and Freedom in Kurdistan (KADEK) in an unsuccessful attempt to thwart sanctions - said it was no longer fighting for self-rule in Turkey and urged Ankara to open dialogue.
But it said it would not disarm.
The PKK, which declared a ceasefire in September 1999 after the capture of its leader Abdullah Ocalan in February of that year, changed its name to KADEK in April 2002, and vowed to pursue democratic means to resolve the conflict with Turkey.
Turkey holds the group responsible for the death of about 36,500 people, many of them rebels, killed in fighting since 1984, when the PKK took up arms for self-rule in the country's mainly Kurdish southeast.