UPDATE 4-Too soon to say if Britons can take summer holiday abroad, says UK's Johnson

* Summer holiday abroad? Too early to know, UK says

* UK to have traffic light system for travel

* International travel will not start before May 17

* England's economy to start to reopen from April 12

* Johnson to raise a pint on April 12
(Adds quotes)

By Kate Holton, Alistair Smout and Elizabeth Piper

LONDON, April 5 (Reuters) - British Prime Minister Boris
Johnson said on Monday it was too soon to say whether
international summer holidays can go ahead this year, a remark
suggesting a planned reopening of outbound travel could be
pushed back beyond May 17.

Britons are among Europe's highest spending tourists so the
fortunes of the continent's summer season and the travel
industry, hit hard by restrictions imposed on travel because of
the COVID-19 pandemic, will depend on when tourists can return
to the beaches, cafes and tavernas of southern Europe.

Britain plans to use a traffic-light risk system for
countries once non-essential international travel resumes, but
the government said it was too early to say which countries
could be given the green light that would only require
coronavirus tests before and after travel.

"Taking into account the latest situation with (coronavirus)
variants and the evidence about the efficacy of vaccines against
them, we will confirm in advance whether non-essential
international travel can resume on 17 May, or whether we will
need to wait longer before lifting the outbound travel
restriction," a government review said.

Johnson told a news conference he was hopeful that
non-essential international travel would restart from May 17,
but that he did not want to underestimate the growing number of
COVID-19 cases elsewhere.

"Obviously we are hopeful that we can get going from May
17th, but I do not wish to give hostages to fortune or to
underestimate the difficulties that we are seeing in some of the
destination countries that people might want to go to," he said.

British media suggested countries on the green list,
requiring testing before and after travel, could include
Portugal, Malta, Israel, the United Arab Emirates and the United
States.

Under Johnson's original plan, international travel would
not resume until May 17 at the earliest. Countries on the amber
list would require self-isolation. Those on the red list would
require quarantine.

Airlines such as easyJet, Ryanair and
British Airways, plus holiday groups such as TUI
, hope to avoid a second lost summer but COVID-19
cases have risen in continental Europe.

Johnson said a planned reopening of the economy could take
place next week, with the opening of all shops, gyms,
hairdressers and outdoor hospitality areas in England.

VACCINE PASSPORTS

With the vaccine programme rolling out rapidly across
Britain and infection numbers falling, Johnson said England
could proceed to Stage 2 of his roadmap out of lockdown from
April 12.

"On Monday the 12th, I will be going to the pub myself - and
cautiously but irreversibly raising a pint of beer to my lips,"
Johnson said.

Britain said people should continue to work from home where
they can and minimise domestic travel.

Johnson also confirmed that the government was looking at a
COVID-19 status certification system, or vaccine passport, to
help reopen larger events and to travel.

"I want to stress that there are complicated, ethical, and
practical issues... raised by the idea of COVID status
certification... using vaccination alone," Johnson said.

"You've got to be very careful in how you handle this and
... don't start a system that's discriminatory."

People will not need vaccine certification for pubs,
hairdressers and shops, Johnson said.
(Editing by Guy Faulconbridge and Timothy Heritage)