Sept 23 (Reuters) - China Yangtze Power Co Ltd on Wednesday launched a secondary London listing to raise up to $3.4 billion, cementing a strong post-summer period for stock market listings and providing a boost for financial ties between Britain and China.

In what would be the biggest deal under a Shanghai-London stock connect scheme, Yangtze Power said it plans to list 110 million global depositary receipts (GDRs) on the London Stock Exchange between $26.46 and $30.95 apiece.

This sets the targeted proceeds at between $2.91 billion and $3.40 billion. The deal is set to price on Wednesday and to list on Thursday, one of the most rapid timetables for a stock market listing.

"This deal has been in the works for a good while yet, but it is encouraging that it is going ahead in spite of an uncertain political backdrop," said a source familiar with the matter. "Regular listings of this nature are going to help financial ties between the countries."

In December last year, China blocked cross-border listings between the Shanghai and London bourses because of political tensions with Britain over the Hong Kong protests, sources told Reuters.

Since then -- and especially in light of tensions with the United States -- China has been keen to revive the scheme, and China Pacific Insurance Co completed a $1.8 billion secondary London listing in June.

The deal will also help bolster the European market for stock market listings, which took a battering in the first half of the year, but has come back strongly since summer.

The Hut Group completed a high-profile London listing last week and a number of different IPOs are being marketed across the continent.

Yangtze Power is the world's largest hydropower company with a market capitalisation of $64.9 billion in Shanghai.

Goldman Sachs, UBS, Huatai Financial Holdings and CLSA are global coordinators on the offering. (Reporting by Muvija M; editing by Jason Neely and Bernadette Baum)