UPDATE 2-Election polls thrust UK midcaps to 14-month high

* FTSE 100 up 0.1%, FTSE 250 up 0.2%

* Aviva steepest decliner on main board

* Pound gains on election hopes

* IQE tanks after results warning

* Buyout offer spurs Consort Medical (Adds news items, updates to closing prices)

By Muvija M and Shashwat Awasthi

Nov 18 (Reuters) - UK mid-caps closed at their highest level in nearly 14 months on Monday, boosted by polls pointing to victory by the ruling Conservatives in upcoming elections, while a near 5% drop in insurer Aviva weighed on the main board.

The domestically-focused FTSE 250 index rose 0.2% while the FTSE 100 added 0.1%.

A win by the opposition Labour Party "could cause turmoil on the markets given the party wants to renationalise several sectors and shake up taxes," Russ Mould, investment director at AJ Bell, said.

"However, a lot can change in politics in three weeks so the markets are likely to remain volatile right up to the big vote."

The bluechips ended higher after their worst weekly performance in four despite a fall in oil majors, as investors pooled their money into the so-called defensive stocks that are perceived less risky at times of uncertainties.

Contradictory reports on Washington and Beijing's trade dispute kept the market on edge. Chinese news agency Xinhua said China and the United States had had "constructive talks", while CNBC reported that U.S. President Donald Trump was reluctant to roll back tariffs.

Defensives from healthcare giant AstraZeneca to consumer goods company Reckitt Benckiser gained, despite rises in the pound.

Aviva fell 4.6% to its lowest point since October after the insurer said it would keep its operations in Singapore and China amid speculation of a sale of the Singapore business.

"The fact that they have not been able to get a bid for it or come to an agreement to sell it would lead you to believe that they were unable to sell it so it isn't worth what they think it is," a trader said.

Among smaller companies, IQE plunged 23% after the tech firm warned on results amid issues with two of its main customers. Consort Medical sky-rocketed 44% past the 10.1 pound a share level on a bid from Sweden's Recipharm .

Biotechnology firm Puretech jumped 14% to top the FTSE 250 index after its affiliate Karuna Therapeutics said its experimental treatment for acute psychosis in schizophrenia met key goals in a mid-stage trial. (Reporting by Muvija M, Shashwat Awasthi and Indranil Sarkar in Bengaluru; Editing by Shailesh Kuber and Andrew Heavens)