The party's pledge to address the GP workforce crisis followed pledges from both the Conservatives and Labour to boost GP numbers as the campaign for the 12 December general election began.
The Liberal Democrats have set out proposals to increase NHS funding by £35bn over the next five years, raising £7bn of this by adding a penny on income tax.
A capital fund worth £10bn would also be rolled out under the party's plans to 'upgrade equipment, ambulances, hospitals and other NHS buildings and bring them into the 21st century'.
A statement from the party said: 'We need to protect our NHS. Under the Conservative government, it's struggling to cope with severe staff shortages, chronic under-funding and crumbling hospital buildings.'
It said that any form of Brexit that ended free movement 'would make it harder to attract nurses and doctors from the EU'.
Around one in 20 GPs in the UK were trained in European countries, GMC figures show. GPonline revealed last week that the prospect of Brexit has already had an impact on the workforce - with fewer European GPs registering to work in the UK and an increase in those leaving since the 2016 referendum.
In the full Liberal Democrat manifesto, the party will promise to 'transform our mental health services by treating mental health with the same urgency as physical health'.
The party said it would 'tackle the severe staffing shortages across the NHS and end the current shortfall of GPs within five years. This will be done by retaining free movement including for the 65,000 EU citizens working in the NHS, reinstating nursing bursaries and establishing a national workforce strategy to match training places to future needs'.
Support for the Liberal Democrats among GPs has risen since the last general election, GPonline polling suggests - with nearly one in three GPs planning to back the party on 12 December.