战争，无论何种形态都会有第三方，而第三方行为受战争环境和交战方身份的影响。在乌克兰战争中，第三方既是调节者，又是冲突直接或间接的相关方。

受战争环境的影响，乌克兰战争中的第三方由三个相互关联的部分组成，即核心国家、中心国家和边缘国家。核心国家是指中国、美国、英国、法国、德国、意大利、加拿大、日本8国，中心国家则是除G7外的北约成员国、集体安全条约组织成员国、伊朗和朝鲜，边缘国家由上述国家外的全球南方国家组成。随着乌克兰战争向长期化发展，第三方行为已逐渐成为影响战争走势的关键因素。

“最强大的第三方”

毫无疑问，“G7-北约”组合是乌克兰战争中“最强大的第三方”，它由33个发达经济体组成，占全球GDP的35%以上，占全球总人口的13.5%，G7则是这个第三方的决策核心。自战争爆发以来，G7始终站在乌克兰一边。在乌克兰战争两周年之际，G7在其联合声明中重申了对乌克兰的支持，并表示要继续提高俄罗斯的战争成本。但是，G7内部存在着诸多影响战争走势的不确定性，比较突出的是来自美国两党的政治斗争。为了减少美国两党争斗对乌克兰战争的负面影响，英国、法国、德国、加拿大、意大利、部分北约成员国与乌克兰签署了10年期的双边安全协定，并开始讨论向乌克兰派驻北约军队的可能性，以此向美国和俄罗斯表达自己支持乌克兰的决心。显然，“最强大的第三方”在行动上的高度团结能让乌克兰战争早日走出不确定性，反之，乌克兰战争前景将愈发不可预见。

“实力不足的第三方”

与冷战时期的苏联相比，俄罗斯依靠的第三方实力较弱，属于“实力不足的第三方”。在过去两年的战争中，俄罗斯以牺牲国家现代化为代价与“最强大的第三方”对抗。然而，根据IMF统计，2023年“实力不足的第三方” GDP总量大约占世界的3.23%，人口仅占世界总数的2%。在“实力不足的第三方”中，白俄罗斯、伊朗和朝鲜的军事支持让俄罗斯在乌克兰战争中保持了一定的军事优势，而其余“实力不足的第三方”则利用西方国家的制裁漏洞让俄罗斯获得了军民两用物资。国际金融协会（IIF）首席经济学家罗宾•布鲁克斯统计发现，亚美尼亚对俄罗斯的出口比战争爆发前增长了430%，哈萨克斯坦出口增长了1200%、吉尔吉斯斯坦出口增长了1200%、乌兹别克斯坦出口增长了1600%，这些国家的商品最终都流向了俄罗斯。但在美国和欧盟越来越严厉的经济制裁下，大部分“实力不足的第三方”将尽量降低军民两用物资出口到俄罗斯，这将迫使俄罗斯增加战争成本。

特殊的“核心第三方”

因中俄关系、经济体量和人口总量，中国在乌克兰战争中属于特殊的“核心第三方”。但是，在过去的一年中，中国政治解决乌克兰危机的方案并没有被各方采纳。G7联合声明（2月25日）和普京国情咨文（2月29日）中没有提及中国方案的内容，G7联合声明甚至把矛头对准了中国。出于早日解决乌克兰危机的目的，中国政府欧亚事务特别代表李辉大使于2024年3月再次访问战争中的当事方和第三方，与2023年5月首次出访不同，李辉访问首站从乌克兰变为俄罗斯。但在访问俄罗斯期间，李辉仅与俄罗斯副外长加卢津进行了会谈，而去年俄外长拉夫罗夫、副外长鲁登科、加卢津都与李辉进行了会谈。

从乌克兰战争环境和当事方对自己的身份认知来看，中国政治斡旋的空间非常有限。而作为特殊“核心第三方”，中国所处的国际政治经济环境将面临更多的挑战。中国企业首次被列入欧盟的经济制裁名单，中欧关系或将发生重大变化，并影响到中美关系。可以说，乌克兰战争延宕加剧了国际体系的竞争烈度，越来越多的第三方国家会被这个充满风险的体系捆绑其中，无法置身于战争之外。对于中国而言，需要更加审慎地评估乌克兰战争，规避减轻各种风险，维护国家利益，早日让乌克兰走向和平之路。这要求中国不仅要权衡自己的社会和经济适应能力，还要选择更加灵活、务实的战略，以服务于中国式现代化。

There are always third parties in war no matter what form the war may take. The behavior of any third party is influenced by the battlefield situation and the primary warring parties. In the Russia-Ukraine war, third parties are mediators and direct or indirect parties.

They are either at the core of the conflict or hold a central or peripheral position. Those at the core include China, the United States, Britain, France, Germany, Italy, Canada and Japan; those at the center are NATO members except G7, members of the Collective Security Treaty Organization, Iran and the DPRK. Peripheral parties are from the Global South. With the war being protracted, how third parties may behave has gradually become a critical factor shaping the course of the war.

Strongest third party

Undoubtedly, the G7-NATO combination is the most powerful third party in the Ukraine war. It consists of 33 developed economies, accounting for more than 35 percent of global GDP and 13.5 percent of the world's population. As the decision-making core, the G7 has stood firmly on Ukraine's side since the outbreak of war. On the war's second anniversary, the G7 reiterated in a joint statement that it supports Ukraine, and it vowed to drive up the costs for Russia.However, there are many internal uncertainties within the G7 that may affect the course of the war, especially the political struggle in America. To mitigate its negative impact on the Ukraine war, Britain, France, Germany, Canada, Italy and some other NATO members signed a 10-year bilateral security agreement with Ukraine and began to discuss the possibility of sending in NATO troops. This was partly to show the U.S. and Russia that they are determined to support Ukraine. Obviously, a high degree of unity in action within the most powerful third party could steer the war out of uncertainty. If that is not achieved, the war's outcome will be increasingly unpredictable.

Third parties with low strength

Compared with the Soviet Union during the Cold War, Russia now relies on weaker third parties — that is, those “with insufficient strength.” In the past two years, Russia has been countering the most powerful third party at the expense of its own modernization. However, according to IMF statistics, in 2023 the weaker third parties accounted for about 3.23 percent of the world's total GDP and 2 percent of the total population. Among them, Belarus, Iran and the Democratic People's Republic of Korea provided military support allowing Russia to gain certain military advantages in the war. Others used loopholes in Western sanctions to allow Russia access to dual-use supplies.Robin Brooks, chief economist of the International Finance Association (IIF), found that Armenia's exports to Russia increased by 430 percent, to Kazakhstan by 1,200 percent, to Kyrgyzstan by 1,200 percent and to Uzbekistan by 1,600 percent. Those goods flowed to Russia eventually. As the United States and EU apply increasingly severe economic sanctions, third parties without sufficient strength will try to minimize their exports of dual-use materials to Russia, and that will in turn lead to higher war costs for Russia.

Special core third party

Given the size of China's economy, its total population and the state of China-Russia relations, China is a special core third party in the Ukraine war. In the past year, however, its proposal for a political solution was not accepted by all parties. Neither the G7 Joint Statement (Feb. 25) nor Putin's State of the Nation Address (Feb. 29) mentioned anything about the Chinese proposal. The G7 Joint Statement even blamed China.To resolve the Ukraine crisis at an early date, Ambassador Li Hui, special representative of the Chinese government for Eurasian affairs, visited the warring parties and some third parties again recently (March). Unlike the first visit in May last year, Li's first stop this time was Russia, where he talked with Russian Deputy Foreign Minister Mikhail Galuzin. He met Russian Foreign Minister Sergey Lavrov, Deputy Foreign Minister Andrey Rudenko and Galuzin during the previous visit.

Given the current battlefield situation and the warring parties' self-perceptions, the space for political mediation by China is very limited. As a special core third party, it will face a more challenging international political and economic environment. As Chinese enterprises are put on the European Union's economic sanctions list, China-EU relations may well undergo major changes, while possibly affecting China-U.S. relations. Arguably, the protracted war in Ukraine has intensified competition in the international system. More third parties will be tied to the risky system and find themselves unable to stay out of the war.For China it is necessary to evaluate the war in Ukraine more carefully. It must avoid and mitigate risks, safeguard its national interests and put Ukraine on the road to peace at an early date. To this end, China needs to weigh its social and economic adaptability and choose a more flexible and pragmatic strategy in the service of Chinese modernization.