This happened after response to the use of chemical weapons by Assad and following US strike at Syrian airbase, and after very hard debates with accusations from Washington towards Russia in the UN Security Council that Moscow supports Assad and in no way prevented the use of chemical weapons.
If you take the international diplomatic dimension, then in principle during the visit of the Secretary of State, who has the level of the Minister of Foreign Affairs, to another country his meeting with the leader of the state, in this case - President Putin - is not mandatory.
At the same time, this meeting was originally planned, and this was the evidence that Putin himself is interested in a direct dialogue with the United States and he is interested in a meeting in the nearest future with the newly elected President of the United States Donald Trump, and that he thus tried to establish himself as one of the world leaders.
Therefore, one more consequence of the cancellation of the meeting of the Secretary of State with President Putin is one more blow to Russia's image in the international dimension after the US missile strike.
At the same time, the visit is still planned. That is, the United States have shown that despite the readiness to take decisive actions, they leave space for dialogue with Moscow and ready to continue discussions on vital issues and problems.
Will the relationship worsen? It is expected that during the visit and the meeting with Lavrov all the issues will be discussed, but it is likely that the dialogue will be built on strong own positions. The United States will speak from a position of strength, the same Moscow will try to do. And everything will end up with a kind of exchanges of views with statements of dissatisfactory, aspirations, goals and so on.
Wherther Putin and Trump's meeting takes place after this meeting in the near future is quite an important issue. If in the nearest future after the end of the visit the exact date of the meeting is not confirmed, as previously they planned to meet in Slovenia, this may indicate the growth of tensions in relations between Washington and Moscow.
If the meeting is confirmed, there will be stagnation for a while. That is, relations will neither worsen, nor improve.
