Over the past week [14], Turkish President Recep Tayyip Erdoğan has been ramping up threats to invade more areas of northern Syria, saying [10] June 1 that he plans to "clean up [the Kurdish towns of] Tal Rifat and Manbij of terrorists," and establish a greater "security zone" in Syrian territory along Turkey's border. Much of this region is controlled by the Syrian Democratic Forces (SDF), which Turkey considers to be a "terrorist organization" because of its ties to the Kurdistan Workers' Party (PKK)—a Turkey-based Kurdish separatist organization. It's not clear if Erdoğan will go ahead with a new incursion now, but some wonder [11] if Western states (such as the US, which has backed the SDF) may be willing to turn a blind eye to such an offensive if Turkey backs off its objections [12] to Sweden and Finland joining NATO. Hundreds of thousands of civilians [15] were forced to flee the last Turkish offensive in northeast Syria [16] in late 2019, and a reported 44,000 to 60,000 people [17] have still not been able to go back home.
From The New Humanitarian [18], June 3.
Note: The 2019 Turkish invasion [19] greatly reduced the Kurdish autonomous zone [19] in northern Syria, with much territory formerly controlled by the SDF [20] and its allies absorbed into Turkey's "security zone [21]." The towns of Manbij [22], Tal Rifat [23] as well as Kobani [19] and Qamishli [24] remain under precarious Kurdish control, in an uneasy alliance [19] with Assad regime forces. Afrin [23] is the principal town held by Turkey and its local allies, but Ankara has maintained open designs to expand [25] the "security zone." Turkey has meanwhile launched an offensive [26] against PKK [26]-aligned forces in northern Iraq.