The phrase "a complex and tense" is correct and usable in written English.
It can be used to describe a situation, relationship, or scenario that is both complicated and filled with tension or stress.
Example: "The negotiations between the two countries have become a complex and tense affair, with both sides unwilling to compromise."
Alternatives: "a complicated and strained" or "a difficult and fraught".
However, the U.S. has had a complex and often tense relationship with Uzbekistan ever since the Andijon massacre in 2005, which earned the Uzbek government widespread international condemnation, and the subsequent closing of the U.S. military base there.
It was in the very decade when Thatcher and Reagan were in power that historians began seriously to deconstruct the wartime relationship between Churchill and Roosevelt — and to show how complex and tense it had been.
Though the roots of the crisis have nothing to do with US politics, Trump's inexperience and rash public statements may have worsened it, and his blunders showcase how unprepared he is to handle complex and tense situations on the world stage.
'"Argo' practically bursts at the seams, but each great character actor has their place, serving a complex and ambitious narrative that expertly juggles political intrigue, tense emotional stakes and Hollywood glitter, resulting in an absorbing and engrossing picture".
It eventually starts to feel repetitive, and suffers from some sizable technical glitches, but XCOM is still a complex, tense and absorbing piece of strategic ET-singeing.
Press reaction was hostile after Hitchcock, far from producing a piece of propaganda, delivered a complex drama as tense dramatically as it was brilliant technically in which the characters, and by implication the audience, are made to face up to what is required to win a war.
The scene marked the culmination of a long-running revenge storyline and Channel 4 said "there was an expectation from viewers that there would be a dramatic end to such a complex tense relationship".
The trial in the courtroom of Justice Carol Berkman of State Supreme Court in Manhattan has proved to be complex and sometimes tense, as it was yesterday when Justice Berkman sustained a prosecutor's objection and told the defense lawyers: "Excuse me, I'm the judge.
Relations with Sri Lanka are complex and often tense.
