Invesco is to take advantage of an unexpected delay in listing its Exchange Traded Fund (ETF) service in London to expand the number of funds available from launch.

The service, provided by Invesco's US ETF subsidiary PowerShares, was due to launch on 12 November but has been held up by problems with registration.

Invesco head of specialist funds Tim Mitchell said the company will now introduce the previously announced three ETFs plus an additional four funds originally intended for launch at a later date, once the registration problems are resolved.

Mitchell said: ‘Because of the delay, we can bunch them up a bit. Between printing our prospectus and registration, we found the FTSE had changed the name of an index.’

An ETF focusing on global clean energy and two based on specialist US indices were originally pencilled in for launch, along with a global water ETF, which the group planned to introduce at a later date.

In addition to these, the company is now believed to be preparing UK services based on its Dynamic Developed International Opportunities Portfolio, its Dynamic Europe Portfolio and an index-based on the FTSE 350.

Mitchell said all seven funds will launch at the same time. The ETFs are expected to be ready for listing within the next two to three weeks, pending approval by UK regulators.

Invesco is launching the ETF range to take advantage of growing interest in these products in the UK.